View Full Version : 3.8 V6 sluggish
A.W.Dille
05-03-2004, 11:49 PM
yes it is nearly two thirty in the morning but I just got done trying to figure out what's wrong with it. It's in an 85 Grand Prix and I found the timing was not advancing so the first step I took was change the computer with no change. Next I changed the control module and wiring harness and rechecked the timing. Sitting still the timing advanced but after a road test it has no power and doesn't seem to pick up any till you back off the gas just a little, but still not responsive enough to maintain a safe road speed. I'm starting to think either a sensor in the carb or some part of the exhaust system is collapsing. I have already replaced the cataylic convertoer with one that's been gutted so I know it can't be that. Anyone got any suggestions on where to go next. Wife has to drive about 30 miles one way to work and I need to figure out quickly what is wrong so the car doesn't quit on her somewhere in the middle of the night. Any suggestions?
A.W.Dille
05-03-2004, 11:49 PM
yes it is nearly two thirty in the morning but I just got done trying to figure out what's wrong with it. It's in an 85 Grand Prix and I found the timing was not advancing so the first step I took was change the computer with no change. Next I changed the control module and wiring harness and rechecked the timing. Sitting still the timing advanced but after a road test it has no power and doesn't seem to pick up any till you back off the gas just a little, but still not responsive enough to maintain a safe road speed. I'm starting to think either a sensor in the carb or some part of the exhaust system is collapsing. I have already replaced the cataylic convertoer with one that's been gutted so I know it can't be that. Anyone got any suggestions on where to go next. Wife has to drive about 30 miles one way to work and I need to figure out quickly what is wrong so the car doesn't quit on her somewhere in the middle of the night. Any suggestions?
1979ta
05-06-2004, 07:01 PM
Hi when the car is idiling does it have power when you hit the gas or does it wait until a certain rpm ?? if the power doesnt come until the rpms are up then you definately have a timing problem timing chain or timing belt might have jumped a tooth...i experienced this before the car will run but no power
mike nixon
05-06-2004, 07:13 PM
check the egr valve to make sure it's not dumping to the full open position.
also check the muffler and see if the convertor that failed plugged it.
mike
A.W.Dille
05-07-2004, 04:34 AM
Mike I don't have to worry about the convertor as it has already been gutted years ago. I had already thought about the egr valve and consulted a friend on that. He came over and checked it out and it turned out another one these computer controlled carbs has turned to junk (again). He disconnected the hookups on the carb and it's doing better but now has a vaccum leak that is driving me crazy trying to find it. Tried everything, starting fluid, carb cleaner, penetrating oil but to no avail yet. I'll be happy when I can get the wifes 69 Custom S up and running and get this Grand Prix out of my gray hair.
george kujanski
05-07-2004, 01:50 PM
You can't just remove the "hookups" from a computer controlled carb and expect it to work correctly.
George