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Old May 26, 2011 | 10:02 PM
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Default idle problems

I have a 1982 corvette which I just got for a birthday present from my wife and I'm having an isssue with it running really rich like it's flooding. It smokes like crazy and wants to stall. It has 76,000 miles on it. when it's cold it runs very rough but when it reaches operating temp it smooths out alot. When I shut it off for about 10 minutes to like get gas and start it up again it idles at about 2000 rpm for about a minute or so then drops down to about 800-1000 rpm. Is there a way to stop this high idle. I did replace the spark plugs because with all the flooding symptoms they were black and fouled. This did seem to help me at least get it to run a little better but this high idling after the engine is already warm has me puzzled. Any input may help. Thinking about rebuilding the TBI's? Maybe injectors
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Old May 27, 2011 | 08:37 PM
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She got a sister?
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Old May 27, 2011 | 09:09 PM
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your coolant sensor in the front of the motor by the water pump is bad.that is your flooding problem.the high idle is a vacuume leakhttp://www.crossfire.homeip.net/index.php?act=idxyou should look into this web site
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Old May 29, 2011 | 08:47 AM
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Default idle problems

Thanks for replying Terry but When I got this there is a new water coolant sensor installed and as far as the vacuum leak I've checked all over and cannot find anything there. When it's warmed up it runs great but after I shut it off for a few minutes and start up again it goes right into a very high idle (about 2200 rpm ) for about a minute then automatically kicks out of that into a stumbling,stalling mode. Then I have to start up again and maybe it will be ok or maybe back inti the high idle thing again. It was told to me that the previous owner also put another computer in it. I'm lost here
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Old May 29, 2011 | 10:38 AM
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if the car runs great after it is warmed up.and it will idle just fine below 900 rpm .then the computer is getting a bad signal .it gets a signal from the front coolant sensor.check the sensor and the wires to it .the computer can be bad .but i would check everything else first..the iacs on the tbs are opening up thats what causes the idle to go up, they are letting in more air.the computer is reading cold.
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Old May 29, 2011 | 11:30 AM
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Terry82, Should I have 12 volts to the coolant sensor when I first start it up?
I have no power going to that sensor or is it less than 12 volts and won't show up with a test light. Thanks again for replying Ron
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Old May 29, 2011 | 08:59 PM
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i have never checked to see if it is getting any voltage .what i would check is what the sensor does when the temp changes.with a ohm meter check it in a cold bowl of water then check it in a warm bowl.i think that would be what the computer would read.there have been several people that have had problems with the wires on these sensors.
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Old May 30, 2011 | 12:03 PM
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Originally Posted by olebarn
Terry82, Should I have 12 volts to the coolant sensor when I first start it up?
I have no power going to that sensor or is it less than 12 volts and won't show up with a test light. Thanks again for replying Ron
These sensors operate on a 5 V reference voltage from the ECM- they never should see 12 V.
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Old May 30, 2011 | 04:27 PM
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Does your Check Engine (CE) lamp light when you put power to the ignition? If it does, is the CE lamp on when the engine is running? You first need to determine if the ECM system is still operational (or not). If it is, then it should capture any trouble codes from non-compliant hardware in the system and would facilitate any troubleshooting work you are trying to do.
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