I have a 2003 SLE and my RPM gauge randomly goes up and down while driving down the highway. There is no power loss or gain when this happens so its obviously not an engine problem. I had the Service Engine Light come on and got a code for a bad sensor that is the crankshaft position sensor. I replaced that and its still doing it. What else could it be???

I assume from your username you have an 85 with a Turbo? If not, knowing your year and model would be a BIG help so we can move your topic to the correct section.

Please don't post Mechanical problems in General Chat.

sorry wrong thing. I'll put it in the right section

Tell us what it is, and we'll move your topic.