...I would first check your fuel pressure, especially when it is erratic. I would then look at the IAC. Sounds like you may have a "lazy" IAC.
Problem at restart.
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From: Commerce Twsp Michigan
Problem at restart.
I have a 91 vert with 150K. When the engine is at normal operating temp and I shut it off for a few minutes, then when I restart it the idle fluctuates between 900 and 1100 rpm or it will start and stall unless I keep the rpms up for 10 to 15 seconds. Once I keep it reved up the idle will smooth out.
Does anyone have any idea what my problem is?
Does anyone have any idea what my problem is?
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From: Cumming Ga
I have a 91 vert with 150K. When the engine is at normal operating temp and I shut it off for a few minutes, then when I restart it the idle fluctuates between 900 and 1100 rpm or it will start and stall unless I keep the rpms up for 10 to 15 seconds. Once I keep it reved up the idle will smooth out.
Does anyone have any idea what my problem is?
Does anyone have any idea what my problem is?
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They were there when I bought the car at the end of 2007.
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From: Cumming Ga
those really don't have problems. start looking at the sensors, Iac etc. make sure its going into closed loop. check fuel pressure at the rail and make sure you are not loosing rail pressure. but, with the erratic idle i would lean towards a sensor. do you have any codes?
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those really don't have problems. start looking at the sensors, Iac etc. make sure its going into closed loop. check fuel pressure at the rail and make sure you are not loosing rail pressure. but, with the erratic idle i would lean towards a sensor. do you have any codes?
The only code I have is in the climate control due to a freon leak (9).
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Joined: Sep 2007
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From: Commerce Twsp Michigan
I have a 91 vert with 150K. When the engine is at normal operating temp and I shut it off for a few minutes, then when I restart it the idle fluctuates between 900 and 1100 rpm or it will start and stall unless I keep the rpms up for 10 to 15 seconds. Once I keep it reved up the idle will smooth out.
Does anyone have any idea what my problem is?
Does anyone have any idea what my problem is?
I will follow up on all these suggestions. I would like to remind everyone that it starts cold just fine.
Le Mans Master
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From: Myrtle Beach SC
St. Jude Donor '05-'06
IAC is Idle Air Control valve near the bottom of the TB. You can get a can of TB cleaner and shoot it into the hole in between the blades. That is where the air goes into the IAC passage. I do mine ocassionally and spray till it stalls the car at idle to fill the passage and let it sit for a few min. If you ever looked in one of these intakes you would be shocked at the "cokeing" that occurs from shutting the engine off and back flow from the pistons into the intake. That is why the back of the TB blades are black. It gets into the IAC passages too.
Last edited by Redeasysport; Mar 2, 2009 at 12:39 AM.
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From: Commerce Twsp Michigan
Typical of a bad FPR after it sits long enough for the fuel to evaporate. Pull the vacuum hose off the intake to it and smell it if it smells like gas it is toast.
IAC is Idle Air Control valve near the bottom of the TB. You can get a can of TB cleaner and shoot it into the hole in between the blades. That is where the air goes into the IAC passage. I do mine ocassionally and spray till it stalls the car at idle to fill the passage and let it sit for a few min. If you ever looked in one of these intakes you would be shocked at the "cokeing" that occurs from shutting the engine off and back flow from the pistons into the intake. That is why the back of the TB blades are black. It gets into the IAC passages too.
IAC is Idle Air Control valve near the bottom of the TB. You can get a can of TB cleaner and shoot it into the hole in between the blades. That is where the air goes into the IAC passage. I do mine ocassionally and spray till it stalls the car at idle to fill the passage and let it sit for a few min. If you ever looked in one of these intakes you would be shocked at the "cokeing" that occurs from shutting the engine off and back flow from the pistons into the intake. That is why the back of the TB blades are black. It gets into the IAC passages too.
Le Mans Master
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From: Myrtle Beach SC
St. Jude Donor '05-'06
~40psi. The key test here is what happens when the engine shuts off if the FP drops quickly either FPR is bad or stuck injector usually especially when there is a hard start when warm condition. Be careful pulling the vacuum line after the rail is charged as it may shoot fuel out.
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From: Commerce Twsp Michigan
~40psi. The key test here is what happens when the engine shuts off if the FP drops quickly either FPR is bad or stuck injector usually especially when there is a hard start when warm condition. Be careful pulling the vacuum line after the rail is charged as it may shoot fuel out.