I fixed my car, and I hated to do it!
08-20-2007, 03:08 PM
#1
Race Director
Thread Starter
I fixed my car, and I hated to do it!
I've finally got the car fixed! 
It was the hardest $75 I spent on the car. It was the ECM, I checked every other thing that I could think of and found no problems.
The car always threw a code 13 o2 sensor since I got it. I tried a known good o2 witch did not help. So I bought a multi-meter and a FSM, then got to work. I checked continuity, grounds, and the sensor. I checked for exhaust leaks. The car had leaking injectors witch I figured was the cause of the code 13, but no. After changing the injectors and trying a known good o2, still the same problems.
I checked out the ECM harness, probed each connector and checked grounds. I used a magnifying glass to look at the soldering on the ECM.
The car had a widely fluctuating idle. I checked for vacuum leaks. Cleaned and checked the IAC, TPS, coolant sensor, grounds, TB.
The car would not go into closed loop mode.
All that is fixed with the ECM. The ECM that was in the car was a reman unit witch made me wonder. The people at tpiparts.net were real nice, $75 for a used ECM that was checked over and known to be good. $18 I will get back for my core.
I had fun with it, it was tough to buy the ECM since there was not a very sure sign that it was the problem. I really thought I had a vacuum leak with that fluctuating idle!
It was the hardest $75 I spent on the car. It was the ECM, I checked every other thing that I could think of and found no problems.
The car always threw a code 13 o2 sensor since I got it. I tried a known good o2 witch did not help. So I bought a multi-meter and a FSM, then got to work. I checked continuity, grounds, and the sensor. I checked for exhaust leaks. The car had leaking injectors witch I figured was the cause of the code 13, but no. After changing the injectors and trying a known good o2, still the same problems.
I checked out the ECM harness, probed each connector and checked grounds. I used a magnifying glass to look at the soldering on the ECM.
The car had a widely fluctuating idle. I checked for vacuum leaks. Cleaned and checked the IAC, TPS, coolant sensor, grounds, TB.
The car would not go into closed loop mode.
All that is fixed with the ECM. The ECM that was in the car was a reman unit witch made me wonder. The people at tpiparts.net were real nice, $75 for a used ECM that was checked over and known to be good. $18 I will get back for my core.
I had fun with it, it was tough to buy the ECM since there was not a very sure sign that it was the problem. I really thought I had a vacuum leak with that fluctuating idle!
08-20-2007, 03:31 PM
#2
Le Mans Master
Congratulations, you did a ton of diagnostics so you weren't really throwing parts at it and the end payoff was worth it. I'm glad you're up and going and able to enjoy it again.
I pretty much forget the ecm is there. I don't know if it would come to mind, as being bad. You did good work.
08-20-2007, 07:08 PM
#7
Race Director
Thread Starter
Thanks guys! It feels good to have got the car sorted out and I had fun learning about the car. I'll miss my little buddy SES light though! 
08-21-2007, 11:43 AM
#8
Race Director
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Good job diagnosing. A huge percentage, 90%+, of the ECMs replaced, are replaced needlessly. Your's was one of the few. Good for you for not giving in at the first hint.
RACE ON!!!
RACE ON!!!
08-21-2007, 04:10 PM
#9
Melting Slicks
Impressive!
Sounds kind of fun or kind of challenging. I am impressed you pulled it off. I hope I don't have to do this. Sounds like an all weekend thing and a case of cold ones!
08-22-2007, 10:18 AM
#11
Team Owner
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I'll miss my little buddy SES light though.
Don't worry. That ****'ll come on again soon enough following another issue!
Don't worry. That ****'ll come on again soon enough following another issue!
08-22-2007, 10:35 AM
#12
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St. Jude Donor '05
Wow, that kind of stuff scares me, no way Id ever be able to troubleshoot something like that. Definitely be at the mercy of some $hop.
08-22-2007, 11:11 AM
#13
Race Director
Thread Starter
Learning to troubleshoot the code wasn't bad at all but it was intermittent which opens up another can of worms. I really spent some time looking for vacuum leaks, who ever heard of a faulty ECM causing a surging idle? There was a lot more I tried to, such as pressing up the ECM connectors to make sure they are tight enough.
I hope nothing else crops up for a little while!
There was a lot more I tried to, such as pressing up the ECM connectors to make sure they are tight enough.I hope nothing else crops up for a little while!
