I pluged my OBD2 scanner into the ECM port. Icon shows connected to OBD port but unable to retrieve MIL codes. Check engine light does come on with ignition turned on. I didn't run a scan on the road test yet. Car does run slightly ruff. Sometimes hard to start. Fuel, fuel pump and air filter replaced. Scratching my head??? Systoms seem to be like a bad coil but not famalier with the 4 cyl. Trying to help a friend. Is ther a ignition control module? (ICM)
After car warms up to temp it shutters and shuts off, after cool down starts aga on 1995 Chevrolet Cavalier
by cman50502013 in Horseshoe Bend, AR on May 18, 2013
1 answer 3 comments
ANSWER by ChevyASE on May 19, 2013
There is an Ignition Control Module, but where it is mounted and what style it is depends on which 4 Cylinder motor you have. A bad Coil will not cause the problem you are describing. Also, you say when its warm it dies, but does it die if you just let it idle and warm up or does it die while driving? Just because the Check Engine light comes on when the ignition is turned on, does not mean the PCM is working. The Instrument Panel Cluster (or the BCM in some cases) is in charge of the bulb check at key-on. And, are you positive that it is an OBD 2 system?
COMMENT by cman50502013 on May 19, 2013
Thks for the reply, I will have to find out with my friend if it only dies when driving or not. My OBD2 plug is the only plug that fits the OBD port assuming it is OBD2 compliant. OBD1 is not the correct matching pins. I doubled checked my scanner on my truck and wifes tracker, all workd fine. But I wonder what may be causing the ECU not to send any codes. It does show connected by a solid icon on screen but reads not able to retrieve codes. I did notice the plugs are on the back side of the engine making it hard to see what kind of coil set up it has etc. When I get back with her I will find out more info. THKS AGAIN<I'll keep you posted!
COMMENT by ChevyASE on May 21, 2013
Ok. Well, it sounds like it is definitely OBD2 then. Check the fuses first; In the Fuse Block (in vehicle) CIG - 15A, CLS/PCM - 10A, PCM/IGN - 10A Underhood Fuse Block PCM - 10A Then check the following terminals/wires on the OBD2 Connector under the dash; Pins: 2 - Class 2 Serial Data Line - Purple wire 4 - Ground - Black wire 5 - PCM ground - Black/white wire 9 - UART Data - Tan wire 16 - BATT + (powered from CIG 15A fuse) - Orange wire Let me know what you find.
COMMENT by cman50502013 on May 21, 2013
Awesome response. In a little while I am going back and do a test run with OBD2 pluged in and see for myself what the symtoms are and monitor all gauges. If it doesn't work I'll check the fuses. Thks a million! I'll keep you posted. I did find it is a 2.2 L engine. I'll get back on here this afternoon. We are getting the weather Oaklahoma,is getting now that was awefull.