I have a 1999 Buick Regal GS with a supercharged 3.8 liter engine and 161,000 miles. I bought the car off of my uncle and he said he would have to change plug wires every month to month and a half because it would start missing so bad. When I first drove the car it would quit on me at red lights and in parking lots, it only seemed to do it at low idle speeds. I live on a hill with a blacktop road and I had to give it a lot of gas just to pull the hill it was missing so bad. The plug wire had a lifetime warranty on them so I replaced them and it stopped quitting on me but I still had a bad miss at random but not as bad it would just be like hard jerks. I added sea foam fuel injection cleaner and had the fuel filter replaced. The mechanic checked the spark plugs and he said they were like new AC Delco. I also cleaned the MAF Sensor (the mechanic told me to and how) because the engine did not run steady at idle and it seemed to help that, but not the miss. Walmart tire and lube told me they could blow my injectors out for $20. Do you think this would help? Could my problem be the plug wires? They are carquest brand 7mm wires. Any help is greatly appreciated.

Welcome to AF!!

It sounds like you other issues besides wires especially if you are changing them so often. First, I suggest new coils and a new ignition module. They are expensive so contact Ed Morad at moradpartscompany.com for a used set. It sounds like the ignition module may be the problem. As for the injectors with 161K miles you may be need a new set along with a new fuel pressure regulator. I also suggest that you purchase a set of OEM plug wires for your car. They are good quality and may cure some of your wire issues.

Thanks for the response. I also forgot to mention that the car only seems to miss after I drive it a while like 15 - 20 miles or so but after it sits a while it seems to be fine again. The supercharger belt is also off could that be some of my problem?

Have you ever had the car scanned to see if the misfires are in one cylinder only or random? If so, please post the results.

I would also do a vacuum test and/or exhaust back pressure test to see if the catalytic converter is blocked up. A blocked converter will cause bad random misfires and loss of power, especially after the car is warmed up.

Lastly, do you know why the S/C belt was removed (bad pulley, tensioner, performance related issue like too much KR, etc...)?

I've never had it checked for misfires. I had a mechanic put my car on a small computer and he told me all that showed up was the MAF sensor.

It may just be me but after I drive the car for a while, it does seem like it is has a loss of power. I drove to town today which was probably around 20 miles and when the car was sitting idle it seemed to sput like it was going to quit at times and the rpm hand would jump up and down then level back out.

I would say that the supercharger belt flew off because I had to replace an Idler pulley that the bearing froze on and the pulley was chewed up. I put a belt on it today but something was making a rattling sound so I took it back off. I'm thinking it may be a bad bearing in the supercharger because that's where the noise seemed to come from.

The noise you hear is the coupler inside the supercharger. It is not serious and is a common problem for all of the supercharges. The repair only costs around $50. So put the belt back on.