[ice127]

My engine has a loud low sound during acceleration, it also vibrates the inside of the car like an old school diesel rabbit. In addition to this the engine revs about 1500 rpm up when I push in the clutch, I have an understanding of car repair but have never heard of this combination of problems at the same time, do you have any ideas where to start.

[coolwaterblvd]

Check and make sure the car is not running super lean IE fuel filter or pump. Also the your TPS sensor may be bad and clean out your MAF meter with electric parts cleaner.

[90MustangLX2.3L]

Do you have an exhaust leak?

[sleeper_inc]

Originally Posted by coolwaterblvd

Check and make sure the car is not running super lean IE fuel filter or pump. Also the your TPS sensor may be bad and clean out your MAF meter with electric parts cleaner.

1979-1990 2.3 mustangs never used MAF

[ice127]

The good news is the vibration was a heat shield that covers the bend from the manifold to the exhaust under the car came loose and wedged itself between the body and the exhaust, sometimes you just overlook the simplest answer.

I still don't know why the engine revs when I push in the clutch, is it just normal with this year?

[sleeper_inc]

Try adjusting your clutch because it sounds like its under load and when the load is taken off it rev's to its current idle speed. But then again IDK