My 87 XR7 with the HO starts great, comes off high idle within 10 seconds and idles very choppy (like it has a big cam)and seems like it would like to stall until it warms up, then it idles pretty smooth. Is there likely a sensor gone bad or what? I just reset the idle speed and adjusted/checked the TPS. I have checked for vacuum leaks and checked for codes (nothing). Replaced my injectors with some from a friend with no change and installed new spark-plugs. It is just a cold idle problem that leads me to believe something electronic is not right(i.e. not telling the PCM that the car isn't warm yet).
O2 sensors?
ECT sensor?
Suggestions??
Tests?
:canada:
Anybody?
Check your ECT. Might be just enough out of spec to run py and not throw a code...
Have you ran codes?
Sounds like it could be a map sensor,when mine went it wouldn't idle for .
ive had the same problem ever since i got mine
ive changed every single sensor and nothin fixed it .YET
ive learned to live with it let me know if you find what is wrong
I agree with Chuck, replace the ECT sensor...
Just tossing this out there because I am still learning diagnosing the 5.0 motor. But I took off and removed my Idle Air Controller this past weekend and hit it with some carb cleaner, and I was kinda shocked at all the junk that came out. Its takes 5 minutes to do and a little bit of peace of mind. But I can see why the ECT would be suspect.