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Discussion Starter · #1 ·
I bought a whole car load of parts and had an engine shipped to a local garage. I posted a feeler here, asking what would be the problems, if any, in dropping a 97 engine into a 93. Coolant neck is the only thing that I was expecting to be a problem.

Here are the parts that I dropped off:

Parts and estimated labor $3100
zero mile 97 Ford 2.5 KLDE
ss headers
clutch
ps axle
O2 sensors
outlaw spacers
top and bottom gasket set
cf_z bushings
misc belts and hoses
full synthetic oil and Corvette oil filter
synchromesh trans oil

The shop got everything together in a few days, and have since been stuck for a number of days, working overtime and through the weekend trying to fix a timing issue.

They have mounted the extra coolant sensor in the new coolant neck, rather than swapping the old one. That was the only problem that I was expecting. They said they also had to swap the old EGR and distributor, the EGR doesn't line up quite right and the distributor is different in the 97. The disty was only about a year old, so no big deal.

Anyway, the problem that they are having is the timing doesn't advance under acceleration. They have tested the cam sensor and crank sensor, which seem to be working fine, also swapping in various parts from the 93 in the process, with no positive gains.

Does anyone have any kind of idea as to what may be giving them such problems? Wednesday will be two weeks that they have had the car.

Thanks
James
 

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Did they use the 93 or 97 distributor. Since it *sounds like* there is spark, must be a 93 distributor as a 97 won't directly work with your 93 harness.
 

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Discussion Starter · #3 · (Edited)
Yep, using the 93 distributor. I had to replace it last Christmas anyway, so it's fairly new, or at least mid-life for these cars :rolleyes:

From what I understand, it starts up and idles fine. Just the timing issue.
 

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Discussion Starter · #4 ·
OK, problem solved.

It was the ignitor in the old distributor that was causing the problem.

The ignitor that was just over a year old and working perfectly in the old engine.

He swapped one from a junk yard and it works fine.

Grand labor total: $1032
 

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Discussion Starter · #6 ·
The ignitor has nothing to do with advance. Time for a new mechanic.
Right. This is becoming more and more apparent.

I wish I had gone into this a little more informed. I posted a feeler thread, asking what differences to expect between a 93 to 97 swap... It turns out the differences are way beyond the obvious distributor and coolant sensor.

I knew that newer systems used OBDII, but didn't know what all that would entail. Now that I have the completed swap and have put over 200 miserable miles on the new engine, the original problem that the guy was trying to troubleshoot by replacing the ignitor is still happening.

I did replace the distributor, though, because I was getting a code 4 when I got the car back from the garage and thought that was the cause of the following behavior:

Under acceleration, the engine is bucking, stuttering, CEL lights up on acceleration, immediately turns off when you let off the pedal. If it is glitching timed right with a shift, the engine feels like it is trying to tear itself free from the motor mounts, it bucks so hard... The only code that is stored now is EGR code 16.

He has the new OBDII EGR mounted and hooked up to the OBDI ECU.

I have read a bunch of threads about deleting the EGR and blocking off the port, just letting it plunge away. I need to use the original EGR from the 93 engine, which I still have access to. I don't want a CEL after around $3400 invested in the last month.

First question:

Is the mounting location different on the 93 EGR than the 97 EGR? I have the stock 93 ECU and a 97 engine.
Would I be able to connect my 93 EGR to the 97 engine and have it actually work, or do I have to block the port off and leave it disconnected from the engine? Again, I don't want a CEL.

Second question:

There is an extra vacuum nipple (intake vacuum) next to the VRIS1 actuator. I don't think that was present on the 93 engine. What do I do with it?
Blocking it off fixes the rolling idle perfectly, but kills the power below 4000 RPM. I think this is the "safe mode" that I have seen referenced in other threads.

When blocking off this extra vacuum nipple, at idle, the car purrs like a kitten right around 650-660, with very little fluctuation. With it open, the idle drops to around 250 and constantly fluctuates up and down +/- 100RPMs.

The mechanic broke off the number one and number two VRIS solenoid nipples and neatly tucked away the open vacuum lines in that mess of vacuum and wiring behind the TB... I have fixed that now.

GRRRRRR. :damnmad: See why I want to fix this myself and not take it back to the shop? The car was in the shop almost two weeks, $1000 parts and labor, and it came back with more issues than it originally had.

What to do about the EGR and the extra vacuum nipple?

Thanks for any helpful responses.
 

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Don't forget the 93 intermediate shaft has 3 bolts whereas the 94-97 only has 2 bolts. You must have already changed this out.
First question:

Is the mounting location different on the 93 EGR than the 97 EGR? I have the stock 93 ECU and a 97 engine.
Would I be able to connect my 93 EGR to the 97 engine and have it actually work, or do I have to block the port off and leave it disconnected from the engine? Again, I don't want a CEL.
The blocks are essentially the same. So you should be able to hook up a 93 EGR valve to a 97 engine.
Second question:

There is an extra vacuum nipple (intake vacuum) next to the VRIS1 actuator. I don't think that was present on the 93 engine. What do I do with it?
Blocking it off fixes the rolling idle perfectly, but kills the power below 4000 RPM. I think this is the "safe mode" that I have seen referenced in other threads.

When blocking off this extra vacuum nipple, at idle, the car purrs like a kitten right around 650-660, with very little fluctuation. With it open, the idle drops to around 250 and constantly fluctuates up and down +/- 100RPMs.
You should never have a vacuum nipple just "open". It should either be capped off or hooked up to something.

I don't remember offhand what a random nipple would be for. What size is it? If it's larger than the typical 1/8" vac nipples, perhaps it's the brake booster hose port..? Otherwise, at least cap it off. The OBD-II IM does have an extra nipple down on runner 5 for the EGR boost sensor. I don't recall any other extra nipples, but it's possible.

Is this a Probe or MX-6 engine? The Probe IMs have a nipple for HVAC which the MX-6 does not (it's not capped, it's just not there at all). Which side is this nipple on? You say VRIS 1, which puts it by the throttle body.. but if it was VRIS 2, the HVAC nipple is right next to VRIS 2 on a DE IM.
The mechanic broke off the number one and number two VRIS solenoid nipples and neatly tucked away the open vacuum lines in that mess of vacuum and wiring behind the TB... I have fixed that now.
FIRED
 

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Discussion Starter · #8 ·
Don't forget the 93 intermediate shaft has 3 bolts whereas the 94-97 only has 2 bolts. You must have already changed this out.

The blocks are essentially the same. So you should be able to hook up a 93 EGR valve to a 97 engine.
Thanks, that's a relief.

You should never have a vacuum nipple just "open". It should either be capped off or hooked up to something.
Right. From what I have found so far, there were 3 wide open nipples when I got the car back.

I don't remember offhand what a random nipple would be for. What size is it? If it's larger than the typical 1/8" vac nipples, perhaps it's the brake booster hose port..? Otherwise, at least cap it off. The OBD-II IM does have an extra nipple down on runner 5 for the EGR boost sensor. I don't recall any other extra nipples, but it's possible.

Is this a Probe or MX-6 engine? The Probe IMs have a nipple for HVAC which the MX-6 does not (it's not capped, it's just not there at all). Which side is this nipple on? You say VRIS 1, which puts it by the throttle body.. but if it was VRIS 2, the HVAC nipple is right next to VRIS 2 on a DE IM.
Sorry, it is a Probe engine.

I thought the number 1 VRIS was on the passenger side and the number 2 is on the TB side. Either way, the open nipple is sticking out of the IM about an inch away from the VRIS actuator on the passenger side and it is the small 1/8" size gold colored metal.

What to do with it?

When I cap it off, the car runs really weak, loss of power, but idles well. When I leave it open, it idles like crap, but does not have the loss of power.
 

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Sorry, it is a Probe engine.

I thought the number 1 VRIS was on the passenger side and the number 2 is on the TB side. Either way, the open nipple is sticking out of the IM about an inch away from the VRIS actuator on the passenger side and it is the small 1/8" size gold colored metal.

What to do with it?

When I cap it off, the car runs really weak, loss of power, but idles well. When I leave it open, it idles like crap, but does not have the loss of power.
Now that I re-think this, you are right, VRIS 1 is the passenger side and VRIS 2 is the one closest to the throttle body.

That sounds like the HVAC nipple. Cap it off and never think about it again.

The car running weaker when the nipple is capped is just because you had two things wrong which is not a good thing. The nipple being open let unmetered air into the system.

Run it for a bit with the nipple plugged. Pull the spark plugs and let us know what they look like... sounds to me like you have a rich condition.
 

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The Probe used Vacuum actuated HVAC controls vs Mazdas electric controls so that's what the extra nipple is.

I can almost guarantee the issue is with the OBDII EGR. Most cars switched to a stepper motor with OBDII but I believe Mazda stuck with vac actuation with a different valve assembly.

it sounds like the EGR is open during acceleration. That would throw the code and cause bucking and power loss.

It sounds like your shop messed up big time but unless this is a performance oriented shop you cant expect them to swap parts and work with aftermarket equipmnt with out issue.

hn I was doing transmission R&R work I HATED when I had to deal with aftermarket stuff. it means you have to throw the book out and learn from scratch.
 
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Discussion Starter · #11 ·
The Probe used Vacuum actuated HVAC controls vs Mazdas electric controls so that's what the extra nipple is.

I can almost guarantee the issue is with the OBDII EGR. Most cars switched to a stepper motor with OBDII but I believe Mazda stuck with vac actuation with a different valve assembly.

it sounds like the EGR is open during acceleration. That would throw the code and cause bucking and power loss.
I am going over there after work today to strip the needed parts off the old engine.

Is it also your opinion that the power loss will sort itself out by fixing the EGR? The way it currently sits, with the nipple open, the car revs and accelerates freely like my old engine did. With that capped, it feels like it's revving and accelerating with half-power. It's a significant difference.

Either way, I guess, once I get the EGR swapped over, I will try driving with it closed off and see.

Thanks again, guys.
 

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I believe the OBD-I and OBD-II EGR valves have different harnesses on them. So if you're using an OBD-II one, I wonder how they even hooked it up to begin with.

Side note, 95 is different than 93/94 even though it was still primarily OBD-I for the entire year of production. I do not recall if 95 matched 96/97, but doubt it due to the addition of the boost sensor.
 

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Is it also your opinion that the power loss will sort itself out by fixing the EGR? The way it currently sits, with the nipple open, the car revs and accelerates freely like my old engine did. With that capped, it feels like it's revving and accelerating with half-power. It's a significant difference.
I'd say the air being let in by the un capped nipple is diluting the EGR gasses being dumped under acceleration in to the intake.

But it's hard to say since I cant say exactly what "mode of failure" the EGR is functioning under.
 

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Discussion Starter · #15 · (Edited)
Well, here's an update... I went back to the shop this evening to harvest the second VRIS solenoid. It turns out he had broken one of the ones on the old engine as well, so there was only one there. I had a spare from when I had broken the nipples off of my number one and purchased a whole block (with vacuum lines attached) from hughes46. I had already replaced the first solenoid with my spare over the weekend and the second one doesn't get vacuum until higher in the revs, so no leak there. I will be replacing the second solenoid tomorrow.

Anyway, that's the easy stuff.

The EGR on my old engine is dismantled, the electronics are MIA. The metal part of the EGR that bolts to the head is still there, but the bolts are completely rounded off. It looks like he may have pulled the electronics out of the old EGR. I'm guessing he tried to (or successfully did) transplant the electronics into the new EGR body... That would explain how it is wired up, I suppose, since the OBDII wire harness is different.

So, anyway, I am going to have to go down to the shop tomorrow to find out exactly what he did and get a functioning 93-94 EGR sourced and mounted.

I would consider that warranty parts and labor, wouldn't you?

[edit]
I talked to the shop and am taking the car back in Thursday to have the original EGR mounted.
[/edit]
 

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Discussion Starter · #16 ·
OK, 4 days in the shop now, I decided to give a call back to find out what's going on...

The car is in worse shape now than when I initially dropped it off to them. It is still doing the hesitation and juddering under acceleration, but now it is giving codes 8, 10, AND 16.

- The new (reman.) disty that I put in is now showing "signs of failure", so I will be swapping that out at Advance for a new one.

- Cleaned the MAF and swapped one from a 93 Probe, but still gets the error code.

- Swapped the IAT sensor from the same 93 Probe and still gets the error code.

- He swapped my old EGR back in and still gets the hesitation and code 16 error.

- He replaced the EGR completely with a new one from the Mazda dealership and still the same error and hesitation under acceleration.

The only thing I know to do at this point is lay hands on a different ECU and see if it all clears up. Apparently, from what he said anyway, all three codes 8, 10, and 16 are somehow related in the ECU, sharing a common ground or something (I was at work at the time, doing other things). The Probe that he has been swapping parts from is an automatic, so the ECU won't swap from that.

Is that the logical next step in this process, replacing the disty and ECU?
 

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The only thing I know to do at this point is lay hands on a different ECU and see if it all clears up. Apparently, from what he said anyway, all three codes 8, 10, and 16 are somehow related in the ECU, sharing a common ground or something (I was at work at the time, doing other things). The Probe that he has been swapping parts from is an automatic, so the ECU won't swap from that.

Is that the logical next step in this process, replacing the disty and ECU?
You can put an ATX ECU in an MTX car as long as both are OBD-I. Look at just about anyone who has done an MTX swap to their ATX car.

Since your car is a 93, you have the sensors necessary to run any ECU from 93 to 95 (OBD-I). Go ahead and use the ECU from the parts car.

Distributor... I have my doubts. Sounds like your timing belt is wrong.
 
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