89 SE running rough since changing plug wires...help???
roozter87
02-02-2004, 08:33 PM
I just bought this 89 GP SE auto w/ 3.1 auto, 129k miles.
I drove it for approx 200 miles without a problem including a 140 mile trip on the highway at about 75mph. The car needed a few minor repairs...cv joint boot, directional switch, heater core, and static heard on the radio which changed pitch and speed with engine rpm's.
I changed the heater core, repaired the directional switch, still running fine.
Then I figured that the static could be due to plug wires going bad, so I replaced the wires. I changed only one wire at a time so as not to mix any. I applied a small amount of silicone dielectric grease to both the plug boots and the coil-pack boots. The car ran fine for a couple of days...short trips, then on this past Sat morning, it stalled after driving for about 2 miles. Prior to stalling, I had it running for about 10 mins for it to warm up, and when I left the house, it was running fine. It didn't give me any indication of stalling out either, I came to a stop at an intersection and then pulled out into traffic, then nothing...it just quit. I coasted of to the shoulder, put it in park, turned the key and it fired right up and ran normal. I got to work, about 15 miles, and it started running rough and hesitating. Touching the gas pedal only caused it to stall. I restarted the engine and it was still running rough, and I had to pump the throttle to keep it running, stalled again. Restarted again and it ran fine!
After work, ran fine almost all the way hame, then stalled again. I opened the hood and it looked like the plug wires were coming off the coil packs. I pushed on all of them and restarted, ran fine the rest of the way.
I figured the silicone grease might be to blame so after the car cooled down, I took of the wires, cleaned each one with contact cleaner to get rid of the grease and cleaned each coil tower and spark plug.
Still doing it, runs fine for a little while, then runs like "crap", then runs good again, the you guessed it, "crap"!
Any Ideas????
Please help :banghead:
I drove it for approx 200 miles without a problem including a 140 mile trip on the highway at about 75mph. The car needed a few minor repairs...cv joint boot, directional switch, heater core, and static heard on the radio which changed pitch and speed with engine rpm's.
I changed the heater core, repaired the directional switch, still running fine.
Then I figured that the static could be due to plug wires going bad, so I replaced the wires. I changed only one wire at a time so as not to mix any. I applied a small amount of silicone dielectric grease to both the plug boots and the coil-pack boots. The car ran fine for a couple of days...short trips, then on this past Sat morning, it stalled after driving for about 2 miles. Prior to stalling, I had it running for about 10 mins for it to warm up, and when I left the house, it was running fine. It didn't give me any indication of stalling out either, I came to a stop at an intersection and then pulled out into traffic, then nothing...it just quit. I coasted of to the shoulder, put it in park, turned the key and it fired right up and ran normal. I got to work, about 15 miles, and it started running rough and hesitating. Touching the gas pedal only caused it to stall. I restarted the engine and it was still running rough, and I had to pump the throttle to keep it running, stalled again. Restarted again and it ran fine!
After work, ran fine almost all the way hame, then stalled again. I opened the hood and it looked like the plug wires were coming off the coil packs. I pushed on all of them and restarted, ran fine the rest of the way.
I figured the silicone grease might be to blame so after the car cooled down, I took of the wires, cleaned each one with contact cleaner to get rid of the grease and cleaned each coil tower and spark plug.
Still doing it, runs fine for a little while, then runs like "crap", then runs good again, the you guessed it, "crap"!
Any Ideas????
Please help :banghead:
martygunn
02-02-2005, 03:17 PM
I had a similar issue a while back. If you're sure the wires are not still coming off the the problem sounds like the ignition control module. It is located behind the coil packs. You will have to remove the coil packs and it will come right off. This is an expensive part though($80). If you can wait I would try to buy one on ebay every GM car from 89 to 96 all used the same one.
I came up with a way to test my ignition system that is a lot cheaper than taking it to any garage. In the electrical department of any Lowes or Home Depot they sell a battery operated "live wire tester" for less than $20. You can use this to check all the spark plug wires to see if one may be bad too. Just turn the tester to the lowest setting and it will beep if there is spark going to the plug.
I came up with a way to test my ignition system that is a lot cheaper than taking it to any garage. In the electrical department of any Lowes or Home Depot they sell a battery operated "live wire tester" for less than $20. You can use this to check all the spark plug wires to see if one may be bad too. Just turn the tester to the lowest setting and it will beep if there is spark going to the plug.
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