I have a bone-stock 1988 Regal Custom with about 150K miles on it. I have done much to keep this car maintained, except for the struts and springs. I am experiencing trouble with the car after it warms up. It seems like the engine RPM is going up and down - sometimes to the point of it stalling out. If I hold the gas pedal a very slight amount down, the problem is resolved. I am not sure if it is possible for me to adjust the idle on this car, and if I do, how do I know it will take effect every time I start the car? Maybe I am completely off what I should be looking into, but anything would help.. Thanks in advance!


What has been done so far:
[New] Borg-Warner Spark Plug Wires
[New] Autolite Copper-Core Plugs
[New] Oil Change (Valvoline Max-Life)

The above seemed to help somewhat, but the problem still persists. Additionally, I have noticed worse and worse fuel economy over the years. I've been putting Premium Unleaded gas in the tank and seemingly helps a lot, but maybe there's some parts out there I can replace and get that smooth purr that she used to have in the late 80's early 90's. -Dale

My 1995 Buick Regal GS, 3.8 L VG, with 55,000 miles on it is doing the exact same thing. I was thinking possibly the O2 sensor or something with the IAC valve. I have already replaced plugs and wires, air filter, fuel filter, and PCV valve, but am hesitant to just start replacing things. My situation is exactly the same, jumps/sputters in RPM's in Idle (any gear) but when a little gas is given (not even 300-400 more RPM's), the problem disappears. I did take it to a shop and it is NOT giving any codes. Any help with this problem would be GREATLY appreciated

Yes ANY help would be good!!

Throw out the autolits plugs they are trash and opnly cause problems. Have you had your battery disconnected recently? If so then the IAC lost its memory.


Ever changed the gas filter, air filter? If not do so.

Have you cleaned the IAC, IAC bore and throttle plate? If not do so.

Thanks for your ideas! I will try out those things this weekend (if the budget allows it) and get back to you here. What would you estimate this costing me? I was recommended to use the Autolite plugs, because the other alternative was Bosch and they were over %400 more expensive. You get what you pay for these days, so back to the Auto store it is =). Thanks for the advice. I will go ahead and get the right stuff to get this Regal on the road like she used to be back in the days.
Can I clean the IAC and the throttle plates on my own?
Oh, I almost forgot, is there any places I can download a .PDF file automotive book for my model Buick? Just wondering.

Thanks a TON!

-Dale

Thanks for the idea's Flatrater. No, I have not tried cleaning the IAC, IAC Bore, or throttle plate, but I will give it a try. Also, you mentioned if the battery was disconnected, the IAC could lose it's memory. How can it be relearned? Is there a certain procedure I could do to relearn the IAC, or would it have to be reprogrammed at a shop?