Idle Surge Issue After Head Gaskets
11-01-2009, 08:51 AM
#11
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Join Date: Dec 2005
Location: Lil' Rhody
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Okay, hoping to get this in the right topic - and hoping someone has the patience for my novel-like detail.
Just recently replaced my destroyed Fel-Pro 1011-2's for Cometic MLS + ARP Head Studs, and I now have Check Engine Light, Idle Surge, and Very Fuel Rich Condition.
Keep in mind the car ran perfectly fine on this setup before the Head Gasket went. It even idled fine on the blown head gasket!
*Car runs fine at first start up, but once it starts to warm up (get into closed loop) it starts to idle surge little by little until it finally dies. While the car is idle surging I have tried pulling the harnesses one by one on the IAC, CTS, and O2's. Vacuum reads -15 during cold idle (before tear down was closer to -17 or -18) but the air/fuel sits around 13.0:1 so I figured the rich condition is causing the low vacuum... (Or do I have a Vac-leak???)
*Cleaned MAF
*I have checked around for vacuum leaks, and to no avail so far. Checked the EGR for the plunger sticking open (but it is not hooked up or hanging open). Tried pulling the IAC and limiting air with two fingers and the car idled perfectly and the A/F was back to normal. During driving the car will move and under throttle car will sometimes pull hard and hold decent vac/(A/F) and other times will load up and fall on its face.
*Set TPS Voltage to 0.99.
*Have replaced Coolant Temp Sensor and O2's as they are the only codes showing in KOER self-tests.
*With KOEO Self-test car only shows one drivability effecting code which is 67, clutch/neutral safety switch. When depressing the clutch pedal with KOEO test running code 67 is eliminated. I don't know if this means 67 is irrelevant or not.
So if anyone has advice to offer then I would highly appreciate any help I can get! I am absolutely stumped!
Just recently replaced my destroyed Fel-Pro 1011-2's for Cometic MLS + ARP Head Studs, and I now have Check Engine Light, Idle Surge, and Very Fuel Rich Condition.
Keep in mind the car ran perfectly fine on this setup before the Head Gasket went. It even idled fine on the blown head gasket!
*Car runs fine at first start up, but once it starts to warm up (get into closed loop) it starts to idle surge little by little until it finally dies. While the car is idle surging I have tried pulling the harnesses one by one on the IAC, CTS, and O2's. Vacuum reads -15 during cold idle (before tear down was closer to -17 or -18) but the air/fuel sits around 13.0:1 so I figured the rich condition is causing the low vacuum... (Or do I have a Vac-leak???)
*Cleaned MAF
*I have checked around for vacuum leaks, and to no avail so far. Checked the EGR for the plunger sticking open (but it is not hooked up or hanging open). Tried pulling the IAC and limiting air with two fingers and the car idled perfectly and the A/F was back to normal. During driving the car will move and under throttle car will sometimes pull hard and hold decent vac/(A/F) and other times will load up and fall on its face.
*Set TPS Voltage to 0.99.
*Have replaced Coolant Temp Sensor and O2's as they are the only codes showing in KOER self-tests.
*With KOEO Self-test car only shows one drivability effecting code which is 67, clutch/neutral safety switch. When depressing the clutch pedal with KOEO test running code 67 is eliminated. I don't know if this means 67 is irrelevant or not.
So if anyone has advice to offer then I would highly appreciate any help I can get! I am absolutely stumped!
Set your TPS between .8 and .9 volts, if you are pulling LESS vac now than you were before, there is an obvious reason for it. your fuel trims have NOTHING to do with the vac you pull at idle. so suspect a leak. Go back and retrace your work, check all your bolts, and reset your ECM. then follow the proper Idle Relearn Procedures (you can find this on google)
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