glenncof

This is kind of dumb but my wife drives the truck and "Always" thinks it will "Blow-up".

Vehicle: 1997 Tahoe 5.7l, 115,000 miles

Background: This truck has always started with a flick of the ignition key. I have had the usual problems with the CSFI injectors clogging causing misfire at start but Techron cleaner seems to do the job.

Problem: Hard starting (relative to the flick above). Tapping accelerator pedal seems to solve problem (no miss-fire so I don't suspect injectors). I suspect idle bypass motor but idle is fine at all other time.

Action: I cleaned the throttle body today with cleaner/toothbrush. Appears not to have helped.

I have a Range Rover with GM engine (factory) and the idle bypass motor gets clogged with oil from PCV blowby which is upstream. Tahoe PVC is also upstream. Could this be happening here ? I'm getting ready to pull the bypass motor but don't know what to expect.

Does idle bypass control air flow during start-up ?

Any similiar expereince ?

glenncof

Well, I pulled the idle bypass motor and cleaned it & the cavity. I put some teflon spray on the motor's plunger.

Started three times without a problem.

bigbluesuvv

I think the government-mandated fuel additives are what causes most of the starting problems. Maybe when they snap out of it and ban MTBE for good our trucks will miraculously be cured.

glenncof

Follow-up; fix confrimed...

glenncof

Problem returned and I replaced AIC valve and fixed problem.