dick_landy
Registered Member
1990 suburban, its got brand new coolant temp sensor,thermostat,o2,tps,map,pcv valve, vacuum lines,vss and reluctor ring,plugs,cap and rotor,timing is set at 0. even has nev valve cover gaskets.
the engine idles around 1000-1200,sometimes 2000 but thats rare.
put it on the scanner and everything appeared as it should with no codes except for the iac was around 39-41 at idle. sometimes shifting it back and fourth from neutral to drive would get the idle to settle down to 700rpm and 500prm in drive with an iac count of 15-20, but as soon as its drivin, it starts to act up again.
things i have tried; sprayed carb cleaner all around intake and tbi base-no change in rpm,swapped iac with 2 known good ones-no change,swapped computer with known good one-no change,reset iac by jumping aldl port etc-no change, coaxing the idle to normal rpm by shifting it back and fourth from neutral to drive then disconnecting the iac- idle stays where it should but cold starts suck and throttle response suffers.
i am totally lost and dont know where to go from here. i can get it to idle nice but by the time i get to the end of the block its back to idleing high.
the engine idles around 1000-1200,sometimes 2000 but thats rare.
put it on the scanner and everything appeared as it should with no codes except for the iac was around 39-41 at idle. sometimes shifting it back and fourth from neutral to drive would get the idle to settle down to 700rpm and 500prm in drive with an iac count of 15-20, but as soon as its drivin, it starts to act up again.
things i have tried; sprayed carb cleaner all around intake and tbi base-no change in rpm,swapped iac with 2 known good ones-no change,swapped computer with known good one-no change,reset iac by jumping aldl port etc-no change, coaxing the idle to normal rpm by shifting it back and fourth from neutral to drive then disconnecting the iac- idle stays where it should but cold starts suck and throttle response suffers.
i am totally lost and dont know where to go from here. i can get it to idle nice but by the time i get to the end of the block its back to idleing high.
