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I never had a problem with my original distributor that came with the car. It lasted for 22 years, and likely would have kept going. But when I was putting all kinds of replacement parts in at the 200,000 mile mark, I decided to get a new distributor also. I guess a lot of drivers are interested in the HEI mod for reliability, but I never experienced that problem.

Now the new distributor with the replacement engine is working well. It has the same firing order as the original KL engine, and the distributor is also a fit for the original 1994 KL engine. That was a complete surprise, because the distributor cap that came with the replacement engine has a completely different firing order marked into the distributor cap ! Starting from left bottom, it goes 5 4 6 3 2 1 around the circle, whereas the distributor cap order for the new distributor, and in the books, is 4 5 3 2 1 6 !!! How can that be ?

I only have a basic understanding of how the ecm and distributor work together to stop the engine when there is a diagnostic problem, or input failure. The secondary cable harness on the distributor has 8 or 9 wires bundled. If one of these, such as the knock sensor, does not send a signal to the distributor, will that shut down the engine, or keep it from starting ? How does that circuit go - the distributor checks for a knock sensor signal, via the ecm, and if not there, will not start ?

The ECU only needs the crank signal for the injection pulse to happen. Prior to 95, the ECU needed cam(dist signal G), cylinder ID(also dist) and crank signals to send the trigger signal to the Ignition control module located into the distributor to have the coil fired. After 95, Mazda got rid of cylinder ID in distributors.

There are many types of distributors on the K series that are not all interchangeable. They also have different components that might or might not fit each other and make your life miserable while you're trying to make sense of it. Also, some JDM KF/KLZE's even came with 7 nipple distributor caps because they had external coils (OEM HEI mod!).

There is no such thing as the ECU stopping signals from happening. It's the other way around actually. The ecu needs signals (see 1st paragraph) before it sends ignition trigger and injector pulse. The ECU also needs to be properly powered.

The knock sensor isn't necessary for engine operation. You can leave it unplugged and run the car. It only sends signal to the ECU when the engine is knocking.

The distributor has between 7 and 9 wires, divided in 2 plugs. There should be a 6 pin plug and a 3 pin plug (even if you don't have that amount of wires. The smaller plug has 3 pins and between 1 to 3 wires depending on model and year. The biggest wire is the 12V, the other 2 are tach signal and diag box pin ign-. Mazda have deleted the last 2 during production. The other plug has between 5 and 6 wires. There should be a switched 12V, 2 or 3 wires to the ECU(G signal, Ign trigger and pre-95, cyl ID) and 2 grounds. The order of the wires on the connectors change throughout the years and should be looked up with your individual model and year.

My theory about distributor failure is that oil leakage from valve covers covers the distributor, seeping in then causing failure of the ICM/coil.. It is mainly due to poor maintenance. Probably add-in overstraining the coil with defective wires and plugs. If you kept yours in good shape and not covered in oil like most KL's I've seen, I'm convinced they could go on for a while.
 

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Discussion Starter #42 (Edited)
Hi Xmaster,

This all makes sense because I too was getting confused when looking at different wiring diagrams between the different years. The CID (cylinder identification) signal as an example was dropped in 95+ (I think, from memory).

What actually causes the distributor to fail, IMHO (which I know from first-hand experience), as I fixed the distributor in my last 94 mx, was the ignition module made by Mitsubishi. The module has a high power transistor that begins to fail (hard to start) then fails completely (crank no start). See my previous post #16 . There are different versions of this module, so you must get the right one to match your specific loom wiring, but they do exactly the same job. I was very nervous when I took the distributor apart (the mechanical part was still attached to the car), but I laid everything out in the right order. My ignition module was the Mitsubishi J888 found here SPECTROMATIC LTD: J888 ignition module MAZDA MX-3

It says Mx-3 but it was the right one for the 1994 mx6 v6 2.5l. Which worked great!

There is a really good explanation of it here ErgonITe - Probe/626/MX6 FAQ - Problem Areas

With a circuit diagram!! (attached)

The main reason for any change was this module!

I know precisely how the distributor works (or doesn't) it uses the "hall effect" sensor (voltage pulse when breaking a magnetic field) when the metal ring on the underside of the rotor arm breaks the field, it send a pulse through this circuit (below) which is then amplified and sent through the coil (basically a transformer in the distributor) which then goes through the rotor arm tip to each HT lead via the distributor cap, in the right firing order. It does not matter that much what is written on the distributor cap (if it is wrong), as long as the HT leads go to the spark plugs in the correct firing order and TDC (top dead centre) is set correctly. That is why mechanics label both the leads and the cap (see Eric the Car Guy on youtube) ... I got caught out on a Mazda 323!! Very embarrassing when I had to take it to a garage who pointed out that the firing order was slightly mixed up and the labelling on the cap wasn't right.

I have an immobiliser on my latest 1996 mx6 I bought after one of my 94 mx's was rear-ended by a new driver (yes I have a 94 MTX in Australia and did have a 94 ATX in the UK). I spent ages trying to remove the ECU on this 96 car, as it had anti-removal screws and an especially made bracket with a metal shield to stop anyone cutting through the bracket to remove it, a clever security feature.

Once I had the ECU out and opened it, I compared it at a circuit level to the NO immobiliser circuit, I discovered an extra programmable chip on the immobilising ECU!! So I strongly believe that given the effort Mazda went to, to prevent the ECU being removed and presence of this chip, that the ECU controls everything for immobilising the car (why wouldn't it!). The key definitely has a chip in it, looks different (fatter at the top) to the standard key.

Because my latest car is automatic, I need to work out the pin mappings for the automatic transmission as well! I have two of the KLP2. (bought on ebay cheap!!).

Any help with a wiring diagram for the 96+ MX6 automatic transmisssion and connector would be great. I cannot find anything anywhere for the Non-US 96+ MX6 (two rows of pins, 12 pins) !! HELP!!

The ECU with this connector https://uk.rs-online.com/web/p/products/1614117/

Thanks
 

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Right now this replacement engine has a new distributor with cap. It has the same spark plug wire position marked that the distributor that came with this engine had. But - we have the spark plug wires hooked up not as this cap is labeled, but instead, have them hooked up as it shows in the Haynes manual for 1994 Mx6 v6. And the car is running great !

I am not even sure if the #1 spark plug wire is sitting under the rotor position when TDC is reached. Haven't looked to see. The #1 wire is not in the same place as the cap indicates.

I understand the distributor releases the high voltage spark when there is an interruption in the lo voltage circuit. I am not sure what mechanism causes the interruption - whether done inside the distributor, by a wheel type interruption, or by the ECU breaking the circuit when it gets a signal to do so.

When talking about the ECU, then it does cause the car not to be able to run if it does not get all the input signals required. But how is that pathway - is the various sensor sending a signal to the ECU, and if the ECU does not receive it, then the ECU sends a signal to the 6 pin secondary wire bundle, disabling the distributor and the car from starting ?
 

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I am not even sure if the [URL=http://www.mx6.com/forums/usertag.php?do=list&action=hash&hash=1]#1 [/URL] spark plug wire is sitting under the rotor position when TDC is reached. Haven't looked to see. The [URL=http://www.mx6.com/forums/usertag.php?do=list&action=hash&hash=1]#1 [/URL] wire is not in the same place as the cap indicates.
Given your car is timed correctly and on crank TDC, the rotor will point to the #1 lead pin in the distributor, regardless of what is written on the cap.

I understand the distributor releases the high voltage spark when there is an interruption in the lo voltage circuit. I am not sure what mechanism causes the interruption - whether done inside the distributor, by a wheel type interruption, or by the ECU breaking the circuit when it gets a signal to do so.

When talking about the ECU, then it does cause the car not to be able to run if it does not get all the input signals required. But how is that pathway - is the various sensor sending a signal to the ECU, and if the ECU does not receive it, then the ECU sends a signal to the 6 pin secondary wire bundle, disabling the distributor and the car from starting ?
The cam(inside dist) and crank sensors sends signals to the ECU when the engine rotates. Given both these signals, the ECU calculates engine position, then sends a trigger signal to the coil to have it fire. This grants the ECU some control over spark, inside dwell time naturally.

What ECU? Immobilizer model or non-immobilizer? (the next part is valid for non-immobilizer models)

Again, the ECU doesn't disable anything. You, at the very least, NEED CAM AND CRANK SIGNALS to the ECU and the ECU to be functioning properly. That's it. And when your ECU gets said signals, it produces injector pulse and ignition trigger.

To verify all of this in one simple step, locate the ignition trigger wire, located between the ecu and distributor (on my 96 mx3 loom, it is orange), on the distributor 6 pin plug. Put an oscilloscope or graphing meter on that wire, back probing the connector. Crank the engine. You should see a square wave pattern. If you do not have access to those, you could manage using a multimeter (analog would help greatly). You will see varying voltage, you shouldn't see full battery voltage either, can't remember what my multimeter shown but it was probably between 2 and 5 volts. Anything lower, I'd test ECU 12 volts and grounds. No signal would make me check ECU function, then individually test the crank and cam sensors.

Everything else is used towards better engine performance and does not make it run, only make it run better (EGR, MAF, IAT, IAC, ECTS, knock sensor, TPS, etc.). You could basically unplug everything other than distributor plugs, crank sensor, injector wiring and still be able to run the engine, although it would run horribly or barely start.

My ignition module was the Mitsubishi J888 found here SPECTROMATIC LTD: J888 ignition module MAZDA MX-3

It says Mx-3 but it was the right one for the 1994 mx6 v6 2.5l. Which worked great!
This is the same as the north american 92 mx3 v6 icm. The later 93-94 ICM has 3 screw holes and then the latest 95+ has 3 screw holes, but only one hall sensor. I think they were all built by Mitsubishi, as many electronic parts have been since the 80's. My 2003 Protege5 came with several Mitsubishi solenoid, sensors, alternator and starter. The yellow plug ECUs were built by Denso, most grey plug ECUs were Mitsubishi, including yours.There used to be Ralliart 323 GTX's in the 80's...

I have an immobiliser on my latest 1996 mx6 I bought after one of my 94 mx's was rear-ended by a new driver (yes I have a 94 MTX in Australia and did have a 94 ATX in the UK). I spent ages trying to remove the ECU on this 96 car, as it had anti-removal screws and an especially made bracket with a metal shield to stop anyone cutting through the bracket to remove it, a clever security feature.

Once I had the ECU out and opened it, I compared it at a circuit level to the NO immobiliser circuit, I discovered an extra programmable chip on the immobilising ECU!! So I strongly believe that given the effort Mazda went to, to prevent the ECU being removed and presence of this chip, that the ECU controls everything for immobilising the car (why wouldn't it!). The key definitely has a chip in it, looks different (fatter at the top) to the standard key.
This chip is the one you need to solder to in order to modify codes inside the ECU. Have a read here, I've finally remembered one of my best finds :

Mazda cars fitted with Thatcham alarm immobiliser as standard

The Xedos 9 TA was the KL equipped car. You can see the immobilizer has been used from 95-2001... My KLK1 ecu had a date from 1997 written on the board. 1+1+1... This is how I figured the KLK1 ecu wouldn't work. I'll take the time one day and try to bypass this chip, that would be amazing!

Because my latest car is automatic, I need to work out the pin mappings for the automatic transmission as well! I have two of the KLP2. (bought on ebay cheap!!).

Any help with a wiring diagram for the 96+ MX6 automatic transmisssion and connector would be great. I cannot find anything anywhere for the Non-US 96+ MX6 (two rows of pins, 12 pins) !! HELP!!
That, I cannot help with. I was never able to find anything else than the weird multi row connectors. Your best bet would be to use your KLK1 ECU pin mapping to repin your harness then use the KL47 ECU. KL47 wiring diagrams are readily available, including the trans harness. Good luck with that!
 

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I have a 1994 MX6 2.5l v6, with the original ECU. For the engine, I have installed a 2.5 l v6 engine from a Japanese Mazda Millenia, year 1999 to 2002, not sure which. Car is running great, with the spark plug wires hooked up to the distributor cap in the original sequence of the 94. Comparing the 2 different distributor caps (one from the 94, and one from the Millenia), the top 3 locations are in the same place. The bottom 3 are close too, with only the #6 cylinder being quite apart.

The cam and crank sensors sent their signal to the ECU - and the ECU sends all its signals to the 6 wires
that sit on the distributor ?
 

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The cam and crank sensors sent their signal to the ECU - and the ECU sends all its signals to the 6 wires
that sit on the distributor ?
This had been explained in great detail in one of my previous posts. There is no more information I can provide at this point.
 

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Thanks everything with the car is good. Now 24 years old. Hope it goes another 24.
(don't know why this shows upside down)

 

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Sorry for the late reply guys, I've been super busy.

So the good news; found a local 94 mazda 626 2.5 v6 which was going to get wrecked, so I snatched the engine wiring and the ECU.
Swapped the ECU and harness and tried to start it. Nothing. Then I had to go to the 626 once more and have a look at the distributor, and it has a different firing order. Haha, didn't expect the firing order to be different when the cars have the same friggin' engine. But anyhow, swapped the distributor and she fired right up.

But since the VAF looks very restrictive, I'm in the middle of swapping to the KL47 ECU and MAF, using some of gwq_uk's old info. Have chopped all the wires to the ECU now, so it will be exciting to see if she starts again after I'm done with the wiring. Also using a curved neck intake to try and squeeze every ounce of power out of her (since it's a folkrace car).

I am wondering a little bit about the VAF/MAF swap. I mean, I have everything I need as far as wiring, plugs, sensors go, but I was wondering a bit about the intake temp sensor. I have seen people using two of the IAT signal wires, and that's cool, but will the IAT wires be correct at the ECU side of things if I follow these notes? Would be nice to get a little more info about that bit.
I have the 3 wire MAF btw. Was also wondering a little bit about the fat red/black wire, it that just needs 12v. I have the fat red/black (MAF pin 1), slim brown/red (MAF pin 2) and a slim black/blue (MAF PIN 3).
 

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Hi Xmaster,

This all makes sense because I too was getting confused when looking at different wiring diagrams between the different years. The CID (cylinder identification) signal as an example was dropped in 95+ (I think, from memory).

What actually causes the distributor to fail, IMHO (which I know from first-hand experience), as I fixed the distributor in my last 94 mx, was the ignition module made by Mitsubishi. The module has a high power transistor that begins to fail (hard to start) then fails completely (crank no start). See my previous post #16 . There are different versions of this module, so you must get the right one to match your specific loom wiring, but they do exactly the same job. I was very nervous when I took the distributor apart (the mechanical part was still attached to the car), but I laid everything out in the right order. My ignition module was the Mitsubishi J888 found here SPECTROMATIC LTD: J888 ignition module MAZDA MX-3

It says Mx-3 but it was the right one for the 1994 mx6 v6 2.5l. Which worked great!

There is a really good explanation of it here ErgonITe - Probe/626/MX6 FAQ - Problem Areas

With a circuit diagram!! (attached)

The main reason for any change was this module!

I know precisely how the distributor works (or doesn't) it uses the "hall effect" sensor (voltage pulse when breaking a magnetic field) when the metal ring on the underside of the rotor arm breaks the field, it send a pulse through this circuit (below) which is then amplified and sent through the coil (basically a transformer in the distributor) which then goes through the rotor arm tip to each HT lead via the distributor cap, in the right firing order. It does not matter that much what is written on the distributor cap (if it is wrong), as long as the HT leads go to the spark plugs in the correct firing order and TDC (top dead centre) is set correctly. That is why mechanics label both the leads and the cap (see Eric the Car Guy on youtube) ... I got caught out on a Mazda 323!! Very embarrassing when I had to take it to a garage who pointed out that the firing order was slightly mixed up and the labelling on the cap wasn't right.

I have an immobiliser on my latest 1996 mx6 I bought after one of my 94 mx's was rear-ended by a new driver (yes I have a 94 MTX in Australia and did have a 94 ATX in the UK). I spent ages trying to remove the ECU on this 96 car, as it had anti-removal screws and an especially made bracket with a metal shield to stop anyone cutting through the bracket to remove it, a clever security feature.

Once I had the ECU out and opened it, I compared it at a circuit level to the NO immobiliser circuit, I discovered an extra programmable chip on the immobilising ECU!! So I strongly believe that given the effort Mazda went to, to prevent the ECU being removed and presence of this chip, that the ECU controls everything for immobilising the car (why wouldn't it!). The key definitely has a chip in it, looks different (fatter at the top) to the standard key.

Because my latest car is automatic, I need to work out the pin mappings for the automatic transmission as well! I have two of the KLP2. (bought on ebay cheap!!).

Any help with a wiring diagram for the 96+ MX6 automatic transmisssion and connector would be great. I cannot find anything anywhere for the Non-US 96+ MX6 (two rows of pins, 12 pins) !! HELP!!

The ECU with this connector https://uk.rs-online.com/web/p/products/1614117/

Thanks
I might have some info, you can check if you have the same color codes.

2A Heated oxygen sensor (front RH) BL
2B Heated oxygen sensor (front LH) BL/B
2C Not connected G
2D EGR boost sensor solenoid valve BL/W
2E Not connected R/W
2F Not connected R/BL
2G Not connected LG
2H Not connected BL/O
2I EGR boost sensor BR/B
2J Not connected BL/Y
2K Heated oxygen sensor (rear RH) P
2L Heated oxygen sensor (rear LH) R

Visualization of the plug:
2K | 2I | 2G | 2E | 2C | 2A
2L | 2J | 2H | 2F | 2D | 2B
 

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So, when I was done with the wiring the car would not fire up. I get injection but no ignition. I have checked the crank angle sensor and the distributor signal and it all seems to be fine. I have one more thing I need to check (the second wire that runs from the distributor to the ecu), and if that doesn't work I will just have to run with the VAF :(
I found out about the VAF -> IAT & MAF wiring, was pretty easy actually. Have measured all wires back to the ecu as well, so I know that's good at least. But it won't do me any good without any ignition. The folkrace season starts in 3 weeks, so I don't have a lot of time to fiddle around with this stuff either.
 

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Yeah boys!

I found the problem, and now she's alive with MAF conversion.
There was three wrong wires on the conversion diagram I used. Found the original MX6 wiring diagram (that's my engine harness type) and the original millenia ECU diagram. And it seems that the KL47 ECU doesn't have quite the same pinouts as the KLK1 at least. Had to put pins in 4H and 4E and wire them up instead of 4G and 4H. The 4H was left unused and the 4G was wired up to C26-10 (TDC signal in distributor, big plug 3rd wire (PINK)).
Then it started right up, so rest of the conversion diagram seems fine. Some headache because of these small ECU differences, but overall the conversion diagram saved me a lot of work. It was the diagram uploaded by gwq_uk some time ago that I used. So thank you for that! You might want to edit the conversion diagram or add some extra text to it if you're still in the game.

Still runs a bit more funky than it did with the VAF, so I probably need to check/sort some things out.

Other mods:
Magnacore 8.5mm plug wires
KL47 MAF
KL47 ECU
KLZE curved neck intake manifold
65mm TB
Ebay headers (good flow)
2.5" straight exhaust
CAI
Adjustable FPR (will be set to 38psi at idle)
Ignition will be set 8 degrees advanced
I'm thinking about playing with the coolant sensor mod as well, have seen it give some gains (5whp actually, dyno tested)

I have seen dyno papers from a KLDE with these mods putting down 179,1WHP, so I'm hoping for about the same. I don't have phe"&/¤% (can't remember the name now lol) intake spacers, but I'm still hoping for 170WHP ish.
Do any of you guys know where I could get a hold of some phe#/("¤ intake spacers? It's supposed to help a lot to keep the manifold itself cooler as well, which would help.

Thanks for all your earlier effort guys, this would have been a lot more time consuming if it hadn't been for you!
 

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Discussion Starter #52 (Edited)
Great news, adjustment to the diagram - DONE!

You mentioned "funky", is something not working?

You mentioned three wires but only talk about shifting two? Do you mean two?

The KLG4 intake is better than the KLZE (long neck), or so I have read. It was on 1998-2002 Mazda 626.
http://www.xtremethings.com/KLDE-ZE/KLG4_Modification.htm

Did you have a two or three pin MAF? (KL47)

Where are you in the world?
 

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My car has been running well. Lately however, sometimes it didn't want to start (electric ok, no engine rotation).
Now yesterday the same thing happened after working in the engine compartment. I get a code 2 (cam sensor) and
code 4 (crank sensor). As these are both related to the ECU getting a signal for these in order to fire the distributor,
what could I have touched in the engine compartment to cause this ?

The wire connections at the distributor plugs look okay and secure.

here are some wires down near the vehicle speedometer sensor (the one with the gear) that I was working with. Can someone
give an idea where I might start looking ? All the wires are encased in jackets, so not visually able to see a bad wire.
 

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Great news, adjustment to the diagram - DONE!

You mentioned "funky", is something not working?

You mentioned three wires but only talk about shifting two? Do you mean two?

The KLG4 intake is better than the KLZE (long neck), or so I have read. It was on 1998-2002 Mazda 626.
DIY -KLG4 Intake Manifold Porting and Modification

Did you have a two or three pin MAF? (KL47)

Where are you in the world?
It's running "funky" as if the TPS or the MAF reads something wrong. Seems way too rich and struggles to rev when I floor it. I have checked all the wires and they seem fine and seem to go where they are supposed to go on the ECU. After a couple of startups it wouldn't even start again until I took out and cleaned the spark plugs. So I don't know wtf is wrong.
I have the 3pin KL47 MAF (yes I have supplied it with 12v from the FPR regulator thingy, and the middle wire is MAF signal while the third is ground).
I am not really 100% sure about the TPS. I have 3 wires that goes where they are supposed to on the ECU, and the last one measures ground. But on one of my original Mazda diagrams it looks like all 4 wires from the TPS goes to the ECU. But from what I can tell it's the heated o2 sensor pin on the ECU. Makes me cringe.

I had to connect a PINK wire that comes from the distributor to 4G (TDC signal in distributor). This was left unused in your diagram as C26-10. Originally in your diagram, 4G was used for one of the crank angle sensor wires, but that was wrong. So C26-10 -> 4G. I can see now that I wrote something wrong in my last post (wrote 4H two times, both as used and unused lol). I had to repin 4H and 4E (as they didn't have pins on my Xedos9 ECU plugs, just as in your diagram). Then C26-24 -> 4E (C26-24 -> 4G on your diagram). And then C26-23 -> 4H (C26-23 -> 4F on your diagram). It was the 4F that was left unused. The C22-8 -> 4N was the only correct wire on your diagram regarding spark/fuel control.
At least that was the case with MY setup, which is a 1997 Xedos9 ECU harness plugs (from a KLL2 ECU), 1993 Mazda 626 engine harness (the same as MX6 as far as I can tell), and a 1995 KL47 Millenia ECU. Hope that cleared it a little bit. I had to change the mentioned things (3 wires) to get spark/fuel control. I based my research on original Millenia 1995 and MX6 1995 diagrams to solve my problems. Combined with the diagram you made of course, it really made it all much simpler, even if it had some flaws in my specific situation.

I'm in Norway :)
 

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This problem turned out to be a slight loose connection at the starter ground wire.

The engine codes given during this problem were code 2 (cam sensor) and code 4 (crank sensor). Now these are cleared. Can anyone advise why these 2 codes are given, when the
problem was with the starter wire ?

Information about this, and what the pathway is, would be helpful in understanding, as I thought these were 2 codes that would be given off if there was a problem with the 6 pin wire plug on the distributor. That has the path to the ECU. I thought these codes would be given if there was an issue between the ECU and the distributor.
 

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Discussion Starter #56 (Edited)
I would recommend that you get your 12V source from the heated oxygen sensor. Trace the wire back to the fuse box under the bonnet.

The MAF has a heated wire, make sure it isn't broken. When air moves over the wire it cools and changes the resistance. And the resistance indicates the mass of air flowing into the engine. If the ECU does not get the correct reading then the fuel / air mix will either be too rich or too lean.

I believe the MAF draws quite a bit of power. Which is why the O2 sensor is the obvious choice. It may not have 12V power anymore, check this at the MAF.

How is the car running now?

I'll update the diagram.

Thanks for your persistence! :nerd:
 

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I would recommend that you get your 12V source from the heated oxygen sensor. Trace the wire back to the fuse box under the bonnet.

The MAF has a heated wire, make sure it isn't broken. When air moves over the wire it cools and changes the resistance. And the resistance indicates the mass of air flowing into the engine. If the ECU does not get the correct reading then the fuel / air mix will either be too rich or too lean.

I believe the MAF draws quite a bit of power. Which is why the O2 sensor is the obvious choice. It may not have 12V power anymore, check this at the MAF.

How is the car running now?

I'll update the diagram.

Thanks for your persistence! :nerd:
Hi again. I've heard people using the power from the fuel pressure solenoid to power the MAF with great success, so that's what I did. Still couldn't get it running right, and because of the lack of time (first race of the season is this weekend) I just had to bite the apple and wire everything back to VAF with the stock ECU :frown2:
When we started it up with the stock setup, it didn't even fire up. So I took out all the sparkplugs and gave them a rub, and it fired up, but was running shitty as hell. Back to the drawing board at that point. We measured the VAF wires and tracked them to the ECU, throttle position sensor, distributor, crank angle sensor and they all seemed good. Then we measured the wires for the injectors. And wouldn't you know it, two of the injectors were wired wrong, causing a total of 4 wrong signals (due to wires of the same colour). The thing is, when I put everything back to stock, I changed the wires one by one, not everyone at the same time. So this problem was present with the MAF setup as well, and was most likely the problem all along. That's what I get for measuring the wires with the multimeter while letting my useless brother keep tabs on which wire is which (he is pretty useless to be honest). And now we have no time to try to change it back to MAF before this season starts, so that sucks. There will be a summer break in the racing schedule, so I think we'll go for the MAF setup then. It will probably take considerably shorter time to get it done the second time around as I have all the notes lying around in the garage.

But on the positive note - even with VAF the car goes like hell and sounds like a motorcycle. Headers and 2.5" straight exhaust with no mufflers sounds like a big ass angry wasp, and it revs really fast just like a motorcycle engine. Since it's an older model 626 the chassis is really light as well to make the hp/weight ratio decent. We built it with a MX3 transmission as well to get a little closer ratios for the track. At the testing last weekend it was faster than a golf 3 VR6 with approx 220hp (at the crank). And the mazda actually handles better than the golf, so there is that :grin2:

I have no doubt in my mind that we will get the MAF setup up and running in the summer break, and the MAF conversion wouldn't even have been a possibility in the first place if it haven't been for your diagrams. So thank you as well! I will be back with updates. Might get some videos of some races as well so I can post on youtube and show you guys if you'd like.
 

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Discussion Starter #58 (Edited)
Good to hear you got it all running again. Thanks for the acknowledgement, it was a load of work. I am originally from Australia but now living in the UK. I have an 1994 MX6 in Australia (as per my signature), and 1996 MX6 here in the UK (which isn't as highly spec'd).

The reason I did this was to make a plug and play adaptor, so you didn't have to repin everything. I would recommend making the adaptor, as on page 6 (Bill of materials)

This (link below) is the female plug. You plug the existing ECU harnesses plugs into this; Wire this to 3 plugs below using the mapping (it has an extra 12 pin socket that can be ignored for a manual gearbox)
https://uk.rs-online.com/web/p/products/161-4117
In Norway - https://no.rs-online.com/web/p/products/161-4117

26 pin male to KL47/KLK1/KLK7 ECU
https://uk.rs-online.com/web/p/products/720-1067
In Norway - https://no.rs-online.com/web/p/products/720-1067

16 pin
https://uk.rs-online.com/web/p/products/720-1038
In Norway - https://no.rs-online.com/web/p/products/720-1038

22 way
https://uk.rs-online.com/web/p/products/720-1067
In Norway - https://no.rs-online.com/web/p/products/720-1067

The connectors for the above plugs 3 plugs (26,16,22)
16 of these (I think it's a minimum of 100)
https://uk.rs-online.com/web/p/products/712-1864
In Norway - https://no.rs-online.com/web/p/products/712-1864

65 of these (again a minimum of 100)
https://uk.rs-online.com/web/p/products/680-5097
In Norway - https://no.rs-online.com/web/p/products/680-5097

Use short lengths of 20 AWG (american wire guage) and 18 AWG wire (will all be different lengths depending on where the need to go. A bit of heatshrink to cover the soldered joints on the female plug.

I may make a couple, and send you one. :surprise:
 

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Discussion Starter #59 (Edited)
If I started making the OBDI to OBDII conversion adaptor, so people with an early MX6 (1991 to 1995) could do a MAF/IAT conversion. What would people pay for one?

You would also need to source a Xedos/Millenia/Eunos - Intake Air Temperature, Mass Air Flow sensor (KL47/KL68) and a Xedos/Millenia/Eunos Engine Control Unit (KLK7/KL68/KL47). from a junk yard.

Benefits... Dyno tested;
- There is a significant increase in hp/torque
- It is turbo ready (the MAF continues to read at higher than normal air flow)
- It is a more modern ECU (faster chips, better design)
- It is ODBII, which sends far more information in real time to any scanner tool.
- Better fuel consumption at wide open throttle.
- Bigger fuel injectors can be fitted (from the Millenia S aka supercharged 2.3l) [needed for a turbo]
- A bigger throttle body can be fitted [KL47] (again from the Xedos/Millenia/Eunos 800) more air more power [hour-glassed to increase air flow]
- A KLG4 manifold can be used to maximise air flow and air/fuel greater, so more power.

I don't know the exact HP gain but I believe it should be around 20hp+ [with my superchip remapped ECU on a totally stock engine, I get +12hp]. With a high flow exhaust probably higher still.

Is there anyone that has done this for a newer 1996+ MX6? (ECU wiring is the same as the Xedos/Millenia/Eunos 800, where as the earlier 1991 - 1995 is completely different, but with this adaptor that is no longer a problem)

Anyone? Bueller?
 

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Discussion Starter #60
Just another thought with an upgrade from OBDI to an OBDII ECU + MAF & IAT (from the Millenia/Eunos/Xedos) ... you could use the wiring conversion to go the opposite way (down grade). Why would you do this? Well, the Megasquirt PNP ECU, from diyautotune.com, which is only for 1993 to 1995 MTX mx6's (aka OBDI) may work on the later model using an adapter or re-pin going the opposite way.

Here is the link to their PNP ECU
https://www.diyautotune.com/product/megasquirtpnp-g2-mk9395-for-93-95-probe-mx6-v6-manual-trans/

Anyway... earlier in this thread someone had success in starting their OBDI mx6 on an OBDII ecu (they chose to re-pin the harness). The reason I haven't done this is my 1994 mx6 (OBDI) is in Australia, and I am now in the UK with a later model 1996 OBDII mx6. If I could justify the Megasquirt (for turbo applications?), it is possible to re-pin the harness to work with the Megasquirt (but only for a MTX)
 
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