1992 Chevrolet S-10

Engine Performance problem
1992 Chevy S-10 6 cyl Two Wheel Drive Automatic 186294 miles

my 92 s10 4.3 vin z has a proublem, if you tap the gas it will rev then rev to about 2000 rpm then come down slowly it had a m.a.p sensor code a while back so i tightend the intake manifold its the same, i sprayed brake cleaner around the intake no rpm change except at the egr valuve so i replaced the gasket, could it be the intake manifold gasket? Thank you for your time

October 4, 2010.

It could be vacuum but it sounds like that has been checked pretty thoroughly. You could try cleaning the throttle body and back of the throttle plate with a brush and carb cleaner but judging by the mileage you have, the throttle body may be just to worn out to seal all the aiir out.

Oct 4, 2010.