1991 Oldsmobile Cutlass high idle

First thing you need to do is have the codes read, Autozone does it free, Post the results with the code number(s). Even if the service engine light is not on, there should be freeze frame data stored.
If it won't make it to Autozone, buy a cheap scanner, they can be had for 30-40 dollars, a good investment, since they cover all cars sold in the USA from 96 on...

[quote:5c8e2d24bc="merlin2021"]First thing you need to do is have the codes read, Autozone does it free, Post the results with the code number(s). Even if the service engine light is not on, there should be freeze frame data stored.
If it won't make it to Autozone, buy a cheap scanner, they can be had for 30-40 dollars, a good investment, since they cover all cars sold in the USA from 96 on...[/quote:5c8e2d24bc]

autozone can only read codes from 1996 & newer. is there any one thing that is common to cause a problem like this?

you can use a paper clip to jump the diagnostic conector. Get a chilton manual or the like and it will tell you how to read the flashing lights. they will blink out your code. top of my head i would say you have a vacum leak you can buy a code key also look on ebay

Cross these two terminals as shown, then turn the key on. Count the flashes, a 22 will flash as 2 flashes then a short pause, then 2 flashes, if more than one code is stored, the pause will be longer. The codes will display three times and end with 12. Write them down and post here. This connector is right under the middle of the dash...