so this is a little oddity that i've noticed over time. Its the most inconsistent thing i've ever seen..ie. it happens every once in a while. haven't been able to diagnose circumstances or situation which it happens. but its like this:

I'll be driving (5spd) and either get out of gear to coast to a red lite in neutral or ride the clutch to a stop sign, and my RPMs start bouncing up and down between idle and about 2000. If i stop to watch it, it will usually go on for at least 30 seconds. The tach doesn't settle, its just up and down, up and down..with NO throttle being applied. Very strange.

I've been told that it MAy be electrical interference to the throttle body (which seems plausible since its drive by wire TB)...and that a grounding kit may help to curtail the problem.

Anyone else notice this or have any ideas suggestions. I'm taking the car into the dealer (AGAIN) for other various problems tomorrow, but I'D like to know what is up with it first.

 

I havent had anything like that happen but. Sometimes when i get off the freeway after a bit of driving my RPM dips down to around 500 and stumbles for a few seconds, then goes back to normal.

 

Do you have a CAI? When I had mine, it made my car do just what you've explained. So I took the thing back off my car and problem solved!

 

Yea i have the Injen CAI. Its only done it like 3-4 times in a month of having it on, so im not worried. The last time it did it was about a week ago.

 

I have stock air intake system

 

I kind of have been having a similar problem. Sometimes when I start my car my tach wont register. And occasionally while driving my tach will go eratic (sp) jumping from 2000-5000-0 rpms anyone had this kind of problem?