To start off here is the car: 1994 Oldsmobile 88 Royal, 69, 728 actual miles, 3.8 V6, fully loaded ac,p.s ect. Now here is the problem. The car came from a aunt which allowed mice to get into the dash, 6 dead ones on top of the heater blower box. Yes, I know what mice do. So far, I have found only three chewed wires, which I fixed using new wire solder and shrink wrap. Besides that, this is the problem. The car has a intermittent shut down problem and has started over a year ago. When the problem happens, the injector pulse from the ecm is lost but spark is present at the plugs. I found this out by using a injector noid light tester. Voltage readings and Wiring checked ok from the ecm to the injectors. I have good power and grounds feeding the ecm. After inspection of the engine wiring harness, pin check to ecm, and pin check on the fire wall connection, found everything to meet spec. The problem will happen warm or cold but than can "self fix" its self, may not act up for the next 1,000 miles or happens the next day. Sometimes, it will start right up and other times, nothing at all. Just depends the cars mood. A previous shop had diagnosed the ECM as being fault. Now, if that was not bad enough, it was taken to another shop 6 months ago "before I got the car" and they diagnosed the problem as a faulty ecm. Two faulty ECMs, big red flag! Is something taking out the injector driver in the ecm? Have no idea? Well, after the replaced ECM the car worked great until the cam sensor failed. OHM checked the sensor and found the sensor to be open. Volts/ohm checks to the sensor ok. After the cam sensor was replaced, car ran for 3 months with no trouble. The car does have a ob2 connector but is still ob1 and does not allow for stored codes. No codes present. The crank sensor, cam sensor and coil pack module have been replaced. Alternator and battery pass load test. My thoughts are leading me to a loose wire but what would cause the injector signal to be lost, sometimes come back and other times not at all? I know the button the cam gears can fall off and cause a no start problem, it was there 3 months ago when I put the cam sensor in, is there something i'm overlooking? Can that button walk in and out of place? Any ideas would be great. Can give more info and pics if needed. Thanks
Well dan after 13 yrs at gm I have found a couple of these. one really got me. First I know it sounds funny but you need to pull the carpet back on the dr. and pass. side and check the ground splices as they are connected to every thing in the car from front to back. they are a black connector taped into the harness and connect all the grounds with a steel buss bar. I always cut all the wires and soldered them together and re-tape em up. this problem would sometimes come with the engine dying when trying to roll the power windows down, or intermittent window operation. Second I had one car i really lost my **** on... it would stall on the cust. on HIS dirt road for him at times. I tried a couple of sensors and a ecm as each would look bad depending on the frame the scan tool would freeze on. The only thing that fixed the car was removing all the grounds on the engine and grinding them clean, replacing all the ground ends and reassembling. That prayer i said when the guy picked might have also helped but the car never stalled again and the cust returned for his next two car purchases. this is one heck of a problem you have here-sorry. I have had to wire in lights to the grounds and powers for the injection while driving before also. remember the pink and blk. wires for the injectors is hot with the key on.
good luck..
I BEEN RUNNING AROUND WITH EXTERNAL FUEL PUMP ON MY 1995 OLDS 88 BECAUSE I THOUGHT FUEL PUMP DIED OR THERE WAS SHORT OR BAD GROUND AND THIS GENTLEMEN IS CORRECT THAT SECTION OF GROUND WIRES THAT ARE ON THE METAL GROUND HOUSING ON THE WIRE HARNESS THAT IS ON DRIVERS SIDE UNDER CARPET AND ON KICK STRIP OF DOOR WAS THE ISSUE AND I WAS PULLING MY HAIR OUT BUT I REALLY WANT TO THANK HIM FOR THE RESOLVING MY ISSUE,ALSO WINDOWS QUIT WORKING AND IT FIXED THAT AND POWER SEATS ALSO
THANK YOU NUMBER 1 GM MECHANIC YOU ROCK
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