Engine Performance problem
1987 Chevy Suburban V8 Four Wheel Drive Automatic 160000 miles
After setting all night - fires after about 2 revolutions but will not idle on it's own, I press and release the gas pedetal to keep it going. Once it's warm it is fine, drive any speed-great acceleration and kick down, turn engine off-fires right back up <1 revolution idles slightly higer for 3-5secs then down to regular idle-IAC good.
Changed gas filter, rebuilt TBI filters and gaskets, verified MAP with vacuum meter and voltage drops from 4.7vdc down 1vdc for every 10inches pull, ohm'd out TPS with multimeter- found no dead spots, EGR holds steady when vacumm pulled on it, PCV valve new, However when I remove the rubber hose (one of three) at the front base of the TBI --this one goes over to the filter canister, nothing happens to the idle, I would think that creating a vacuum leak at the base of the TBI --would induce a higer idle? Is this telling me something?
have the same problem?
Monday, February 8th, 2010 AT 10:23 PM