Engine running over 2000rpm while in park

[josh062]

I have a '99 Buick Regal 3.8L Supercharged. I recently had a problem of not being able to start the car. I suspected it was a fuel problem so I got on the forum here and found the Fuel pump resistor bypass post. I tried that and then I tried new relays and neither worked. Then I tried banging on the fuel pump and that got it started. Once I got it started I found a new problem. As soon as it started the engine would rev up past 2000rpm while still in park. I let it run for a little bit and it would fluctuate but still stayed pretty high. I went ahead and changed the fuel pump assembly since I knew that was bad and the problem is still there. There are no warning lights on the dash and there aren't any error codes. If anyone has any ideas I would appreciate it.

[richtazz]

Welcome to AF

I would look for disconnected/broken vacuum lines under the hood as it sounds like a vacuum leak to me. If this only occurred after messing with the fuel pump relay, you may have inadvertently knocked something loose while under the hood. First concentrate your search around the fuse/relay center, then branch out from there.

[BNaylor]

You should have made a post before thinking the fuel pump resistor bypass is your issue. A bad resistor does not normally prevent starting. What you will get is a stall several seconds after starting. What bypass procedure did you use on the fuel pump hi-speed relay? The one for a L67 Grand Prix? If so the fuel pump hi-speed relays where you apply the bypass are not in the same position and marked differently in the Regal main fuse box.

You should run a fuel pressure test with a fuel pressure gauge. On the high idle you could have a dirty or bad IAC.

[josh062]

When it first happened it wouldn't start, then it would start for a couple of seconds like you described. So when I read the resistor bypass post it sounded like what I had. I did use the bypass method of bending tab 85 and I did notice the difference in fuse boxes. The bad thing about the Regal is when you fold tab 85 out it runs right into a tab on relay #19. Since replacing the relay was going to be my next fix if the resistor wasn't the problem I bent the tab over and snipped it off so it wouldn't run into the other relay. The fuel pump ended up being the issue though... oh well, gotta try the cheaper fixes first.

On the idle problem, I drove it a few miles today and it didn't drive to well at first. On straight level ground and without putting any pressure on the gas pedal I was cruising at 45mph. Then after that I parked it and started it again, it started idling fine and drove fine after that. So I think the problem is intermittent and not fixed yet. I'll look into the IAC next and check the vacuum lines like Richtazz suggested. Thanks for all the help! I will definately be visiting this site more often. There's a lot of great info here.

I also have to get a recall taken care of for this car. My Regal smokes a lot from an oil leak and they just came out with Recall 07035 for higher front rocker cover gasket temperatures which is causing oil leakage and the potential for a fire.

Thanks again!

[BNaylor]

Yeah it is best to get that front valve cover gasket recall issue taken care of as soon as possible. Also, when you remove the IAC use throttle body spray cleaner on the spring loaded pintle and lube with silicone spray. Clean the dish part good. Get all carbon off. Do not disassemble the IAC. Then be sure to clean out the orifice/seat at the throttle body where the IAC mounts. For relearn after installation. Take ignition to on for about 5 seconds and then off. Then start car. Good luck.