Hi everyone.

My '99 2.7 runs rough from about 2500 to 3000 rpm. It doesn't seem to lack any power, but it makes excessive noise, almost like something is resonating. I'm also not getting quite the mileage I think I should be. I've already replaced the air, fuel, and oil filters and the spark plugs. I try to avoid using that RPM range, but that's where most normal driving happens so its a pain in the arse. Any suggestions are welcomed.

Thanks,
Tom

 

Does it do it at Idle also? That would eliminate quite a few things. If it does it'd be easy to be under the engine compartment and run the engine up to that range to localize the problem, whether it be internal engine or not. Just a thought.

 

No, it actually idles quite nicely. I've tried revving it up from the engine compartment, but can't localize the source of the roughness at all.

Thanks,
Tom