Why is my 90 silverado not idling good?
My 90 c1500 with a 5.7 is idles fine
wen cold but at operating temp it
starts to idle up an down spittin an
dies. Ses light came on an gave me
code for the cts which i changed no
fix.now i have changed the
coil,distrib, cut the cat off,checked
egr,fuel filter, fuelpump not even a
year old yet.did pressure test on fuel
but both times from two diffrnt fuel
gauged they both leaked at the
fittings do i gave up. An i rebuilt the
tbi. If i rev it up it clears up but then
idles real low then back up an down.
Plz help im pretty mechaniclly
inclined but this has me scratchn my
Sounds to me that a vacuum hose has fallen off and the intake is suckin' air~....could be the connection to the fuel pressure regulator...could be to the egr...could be to the environmental controls~ I'd say an IAT sensor, but I'm not sure this vehicle has one~
always replace the awful black rubber (chewing gum and coal tar) with silicone that never dries out, cracks or swells...these are perfect and totally reliable~
Iv checked all hoses. But none broke or loose.