in my friend's '93 dodge daytona, when he's in drive, if the engine gets up to around 5k rpm, if he lets off the throttle, the revs go down really slowly, and you can hear the engine is staying at a higher rev than it should be.

his dad also said that from the outside, it sounds like the muffler is making a funny noise.

i think it could be a clogged cat, any other ideas?

i posted this in tech/general engine but nobody seemed to know...

 

by the way it's a 3.0 liter v6, non turbo

 

I doubt it.

 

When my old v6 RS had a clogged cat, it had trouble getting to 3500 rpms for what that's worth. The throttle could be hanging open, just a thought.

 

i checked the throttle when he was in the driveway with the hood open, looked fine. could it be any different when it's in drive?