I have a 13 gt track pack. When the engine is at optimal operating temperature, when idling the revs are fluctuating between 600-800 rpm. Is this normal or a vacuum leak?

 

Anyone?

 

is the motor sputtering? Like it's not timed right? Or are the RPMS just changing like there's a control issue?


If sputtering, I don't know. I the RPMS are just changing, then that's a computer issue most likely. Pull the battery cables for a few minutes, re-attach, start-up. See what happens. It's just a basic step you can do on your own. It may or may not help.

 

How many miles? Some say this happens when throttle body and/or MAF needs cleaning.
You didn't provide much info.
How do you drive it - in traffic all the time, all highway, mix of both? Baby it all the time so it loads up? Or do you take it up to redline on a regular basis and blow the crap out of it?

 

I will disconnect the battery.

The motor is not sputtering, it is fluctuating rpms.

Its has 36500 miles.

It is driven mixed 50/50 city/hwy.

I am gentle on the car and rarely drive agressively.

 

I disconnected the battery and it is still slowly fluctuating.

 

If the fuel filter replaceable? If so, I'd start there and also clean the MAF sensor.

http://www.latemodelrestoration.com/...on-FG1083-S197

It is fluctuating because the computer is constantly having to adjust the air/fuel mixture to keep it running. Which usually means it is constantly not getting enough of one or the other. so it fluctuates as it adjusts.

 

I would suspect this ^

Also, look up the throttle position relearn procedure and try that.