1995 Chevy Lumina 6 cyl Two Wheel Drive Automatic 158000 miles
My 95 Lumina Sedan 3.1 L seems to run fine for 3 yrs siince I got it - well maintained before me as well. 2 weeks ago would not start but all else OK. Eventually found it was VATS key resistor sensor in ignition key cylllinder. I did standard key bypass cutting the 2 wires from it at base of steering column & soldering in a resistor of same value as key's. Works excellently. AAll else I did was disconnect battery terminals to clean them & unplug-plug oil pressure sensor harness as it was near srarter, and many fuses & relays one at a time - all while engine was off. Once car started again initial lights in dash work correctly. Then, when engine running (drive it or not) for 7-9 sec or so, Service Engine Light comes on every time. Never at immediate start - just waiting to that delay time of 7-9 sec. My ALDL or OBD1 or OBD1/2 combo connector under dash has only pins A=Gnd & M below it connected to the harness in a pig tail - black & dark or faded yellow or tan, a one colored wire. How do I test why light on? What is sequence of car computer test to get to that moment in its cycle. I tried shorting A=Gnd to M & no codes. Usual A-B short not work because no B pin. Light is on only since I did something on this repair. Same probelm before this was temp light moving up faster than it used to for last 6 months - changed radiator fluid-flushed & will do thermostat. But lSES light never came on for that or anything before, ever. HOW DO I TEST PINS A and M ONLY!
No pins 5.6 etc. My free mechanic friend tested with his GM testor twice and said he could do A G E F B --- and he got no codes out (maybe wrong pins)and tried to turn off light by pulling out EGM fuse and pumping pedals then replacing - light stays out intitally but 7-9 sec in engine running - comes on ech time. I have looked on line no help -and haynes Manual says some 1995 Lumina's do not have pin B and need a scan tool but all those I see require other pins besides GND and M. WHAT DID I DO TO TURN ON THIS LIGHT & HOW DO I TEST MY SYSTEM WITH PINS A & M ONLY. I have searched internetm dealership, auto part stores - to no success.
have the same problem?
Friday, November 14th, 2008 AT 9:39 AM