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Discussion Starter #22
I received the O2 sensors today, will try to put them in tomorrow. But today, I drove 1/2 an hour each way on the expressway, and I noticed the temp gauge went quite high; just a few mm's below the overheat line on the gauge. With regards to that subject, I don't think my radiator is gunked up, or that would have been a gradual change. My water pump is new (with the T-belt job). And the T-stat is pretty recent; several years old, but not that many miles on it; it shouldn't have gone bad this soon. So, I became curious: Perhaps my oil pump is dogging out. I don't know if that could explain the extra heat, and/or, the loss of horse power, but I thought maybe. I've never experienced the loss of an oil pump functioning.
 

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I don't remember reading of many/any failed oil pumps on this board. And I don't think it would cause those symptoms anyway.

How hot is the weather where you are? In very hot weather, and in stop/start driving, if the radiator fans fail to come on that will cause overheating. Otherwise I would suspect a clogged radiator. (You've checked the coolant level of course?)
 

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Discussion Starter #24
Ok; got new O2's installed. I actually think my whole coolant system is fine, and that it is not overheating at all. I was totally using expressway, so it wouldn't have mattered if the fans did not engage; fans come on soon as I start my car from wacky new sensors. So, when I started it w/cold engine the next time, the Temp Gauge went up to normal level immediately. That tells me the new single wire sensor went wonky. (the single wire one feeds the gauge, right?_)
 

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Discussion Starter #26
No closer to figuring this thing out, but I DID want to run by you about the Throttle Position Sensor. I probably haven't searched enough, but thought you might just know the Voltage Range for our cars. I got a new TPS, and it measures the same as the other two I already have (although the car runs hardly at all with it). So, when I calibrate it, I have set it to 0.50 Volts. Then, measuring at Full Throttle, it/they go up to about 3.70 Volts. Are these correct for our cars? Should I be setting it at 0.50 Volts?

So, with the New TPS (that measures the same and is set the same), the car starts, and I was barely able to nurse it around the neighborhood to collect boxes on recycle day. It goes like this: I let go of the clutch while adding fuel, and it moves forward, but then it TOTALLY pukes right after that, and I have to let off the fuel. I was able to get into second gear, but the whole ride around the hood was very dicey.

Changing the TPS was the ONLY thing I did, and that was the result. Rather confusing for me. I haven't tried it since I verified the Voltage measurements were true.
 

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"2. Disconnect the sensor harness at the TPS and check the P wire for +5V with the ignition on......

3. Measure the voltage at the Y wire while slowly opening the throttle by hand (engine off). It should start at closed throttle at about 0.8V and increase smoothly throughout the range of throttle movement......."

The easiest way to set the TPS is the "fan method". Connect TEN and GND pins, turn ignition on, engine off. With the throttle closed the fans should be off. But when you open the throttle by hand, just the tiniest bit, both fans should come on full. Adjust the TPS so that's what happens. (It's rigged that way as a sort of fail-safe cooling.)

Edit: I Googled and found this, which is clearly from the same source I quoted from (It was the famous MikePGT/Dorothy Bradbury document, which used to be linked all over ProbeTalk etc. but doesn't seem to be available online anymore. I have a paper copy.
https://answers.yahoo.com/question/index?qid=20090424194919AAMYCsn&guccounter=1&guce_referrer=aHR0cHM6Ly9kdWNrZHVja2dvLmNvbS8&guce_referrer_sig=AQAAAJYfC-efrO4LrBm7JWUjaEY-z_vTs0Q0jUaE2FJ5Q7nLkto-iN1YOceKeuY1q3TDo4GMID7p1vmj3tLT8NN7PUyeg9IoKGYF-_Ra5izoBKFsS_RpW8Atg7PeGzxD3C4u4zhqqWyqq5ra37OYbCQLd5Qy1YTg875T67oprlQozZCg

Edit 2: see also the last bit of this post. https://www.mx6.com/forums/2g-mx6-general/92406-2g-faq-common-problems-solutions.html#post478915
 

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Discussion Starter #28
Ok, I do have a good +5V at the P wire. Didn't occur to me to check that, even as I was having so much trouble today. I was following someone else's more complicated method for setting the TPS. But, it did lead me to measure the Ohms at the Idle Air Bypass Control Valve, and my reading is out of spec. He gave a range of 10.2-12.3 ohms; mine measured 13.2. Now I'm wondering how bad that is, given my challenges with loss of HP's.

Earlier today, the fans were coming on related to TPS position, but that isn't working for me anymore. But, they do come on right away when I run the engine (pre-maturely, of course).

Re-reading your instructions though, I was NOT opening the throttle by hand, so, I will try again tomorrow.

Oh, the link you gave me was the procedure I was trying to follow today.
 

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Discussion Starter #29
Well, I just tried it, manually opening the throttle, and still couldn't get the fans to kick on. I think I ruined something. But, I will take it out in the morning to see how she runs. I just decided to set the TPS at 0.63 volts because a couple people in that thread had good luck doing it that way.
 

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Discussion Starter #30
Some updates: I finally figured out the correct coolant temp fan sensor to cure my code 69. I also think I was finally able to get the TPS adjusted properly. As for the timing, I recently advanced it as far as it would adjust, and it seems to run a bit better there, no knocking, and it even starts up quicker. But, I still have the fundamental loss of power at higher rpm's issue. Lucky to be able to max out at about 85 mph floored on flat expressways, at about 4300 rpm's with my K8. One thing I never verified was if my VRIS was working properly. I recently changed all my vacuum solenoids because I was able to buy them for cheap, after the combo for the EGR gave me an issue, so, it never occurred to me until now that I might have a problem with my VRIS valves. Tonight I used WD-40 on and in the actuators, will test drive again tomorrow. Not sure yet how to verify their functioning, but think I can figure it out. Chime in on this thread even if not to make input; just want to know if there is anyone left still around, thanks.
 

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You mention 4300 rpm when you reach your top speed of 85 mph. That is the most rpm you can get ?
If so, that is an engine problem, not a transmission problem. These engines can easily rev to 7000 rpm.

Also I don't remember a KLDE engine producing 200 psi at the cylinders. If I remember correctly,
around 150 is the norm.
 
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