PDA

View Full Version : Check engine light



mcate
04-26-2004, 04:34 PM
Don't know what code yet. I'm hopefully taking it over to a friend's house tomorrow to run the code. 1995 SC auto with 36,000 miles. Magnum Powers intake plenum, TB, & C&L 76mm MAF put on last year. Here's the symptoms: While driving around town the check engine light comes on when decelerating. Usually stays on until applying throttle, or if I take it out of gear & the engine speeds up a little. Seems to be running fine, although it sometimes dies while idling at stop lights for extended periods. I'm thinking maybe IAC valve, but I'll know more when I get the code. I was just wondering if anyone's had these symptoms before.

Thanx,
Mike

vancouverBC
04-26-2004, 06:43 PM
The same thing was happening on my 90SC then it did 2 other things to make me change the crank position sensor.
1. It died while I was crawling under idle in traffic. 2. It didn't restart for a while after a lunch, but did show the upshift light on the bottom of the tach. After I changed the CPS, the idle doesn't drop to 500rpm any more and it has not stalled again. Good luck

mcate
04-26-2004, 09:28 PM
Mine restarts fine after it dies. Not hard to restart at all.

vancouverBC
04-26-2004, 10:44 PM
Mine restarted fine after it died except 1 time. Originally I thought it was an air leak and I did find 1 after the pcv valve but the idle still kept dropping and stalling. Try cleaning the connector for the crank sensor, I just replaced mine so I don't have to worry about it. Good luck

mcate
04-27-2004, 04:49 PM
Ok, just ran the KOER test & here's what I got:

121- TPS-MAF not consistant
136- Lean left side
167- TPS change too low during dynamic response test
172- Heated O2 sensor. Lean bank 1

I've gotten the 121 before, last year right after installing the Magnum Powers 85mm throttle body. Had to buy a different TPS because the stock one wouldn't fit flush into the MP TB. I haven't checked the TPS voltage yet. I'll probably do that next. Any other ideas?

vancouverBC
04-27-2004, 08:02 PM
Great, hopefully that is it, if you have a K&N filter with too much oil on it will throw the MAF sensing off. I generally take the electronics off and spray the wires with intake cleaner. Also check for air leaks else where. But mine is stock size etc. Good luck

speedyg
04-28-2004, 12:49 AM
Don't know what code yet. I'm hopefully taking it over to a friend's house tomorrow to run the code. 1995 SC auto with 36,000 miles. Magnum Powers intake plenum, TB, & C&L 76mm MAF put on last year. Here's the symptoms: While driving around town the check engine light comes on when decelerating. Usually stays on until applying throttle, or if I take it out of gear & the engine speeds up a little. Seems to be running fine, although it sometimes dies while idling at stop lights for extended periods. I'm thinking maybe IAC valve, but I'll know more when I get the code. I was just wondering if anyone's had these symptoms before.

Thanx,
Mike

Mike this same problem has been bothering me for a while. My codes point to a lean bank as well. I have put in brand new O2 sensors and a brand new Iac both have which have not helped. Although after each repair while I had the battery unhooked, the car runs better. But then it relearns a few days later and it starts to die or at least drop idle when I come to a stop. If you figure it out let me know,or at least post it here. Here is an old thread describing something similar.


http://www.sccoa.com/forums/showthread.php?t=39616

mcate
04-28-2004, 09:05 AM
I'll let you know what I find, Brandon. I'm going to replace at least one of the O2 sensors today.

mcate
04-30-2004, 12:06 PM
Changed both sensors yesterday, & haven't seen a CE light since. The car did die while sitting at a light idling yesterday, so something is still wrong. But at least no CE lights.