bad idle when hot
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bad idle when hot
nayone know where to start looking for a problem. i read that you need tor eadjust the min idle speed. but just wanted another opinion before i started working on that. the car has 33000 miles and i've already cleaned the iac and throttle body and those seem to be working fine.
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Re: bad idle when hot (runner4404spd)
need more details, but suspect the o2 sensor
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Re: bad idle when hot (runner4404spd)
Mines doing the same thing but only when the a/c is on and slowing down to come to a stop or make a turn. It will surge and acts like it has a miss in the motor. I cleaned my IAC's (way nasty) got better then right back. But when it came back my Air Pump has decided to throw a bearing. Don't know if that is related but any info will help. If you fix your problem. Putting new Air pump on tonight will let you know if that fixes the problem. :D
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Re: bad idle when hot (jennykayes84vette)
the idle will surge and the engine tries to die but then the idle kicks back up and it hunts between 500 and 1000 RPM
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Re: bad idle when hot (runner4404spd)
the idle will surge and the engine tries to die but then the idle kicks back up and it hunts between 500 and 1000 RPM
Wish i didn't have to. We need to get this fix. I will let you know if the Air pump fixes this at all.
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Re: bad idle when hot (runner4404spd)
First, are you getting any SES lights or engine codes, those should be the first thing you check for EVERY time your car doesnt act right.
If there are no codes, I suspect the O2 sensor or MAF sensor. Your fuel mileage will be much lower if its the O2 sensor, you should notice that. My avg mpg is like 16-18 in town and 25hwy, so should yours.
To test the MAF, disconnect it and see if the engine runs better. If the engine runs better its the likely culprit. It would then be necessary to replace the MAF and its relays.
If there are no codes, I suspect the O2 sensor or MAF sensor. Your fuel mileage will be much lower if its the O2 sensor, you should notice that. My avg mpg is like 16-18 in town and 25hwy, so should yours.
To test the MAF, disconnect it and see if the engine runs better. If the engine runs better its the likely culprit. It would then be necessary to replace the MAF and its relays.
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Re: bad idle when hot (vader86)
First, are you getting any SES lights or engine codes, those should be the first thing you check for EVERY time your car doesnt act right.
If there are no codes, I suspect the O2 sensor or MAF sensor. Your fuel mileage will be much lower if its the O2 sensor, you should notice that. My avg mpg is like 16-18 in town and 25hwy, so should yours.
To test the MAF, disconnect it and see if the engine runs better. If the engine runs better its the likely culprit. It would then be necessary to replace the MAF and its relays.
If there are no codes, I suspect the O2 sensor or MAF sensor. Your fuel mileage will be much lower if its the O2 sensor, you should notice that. My avg mpg is like 16-18 in town and 25hwy, so should yours.
To test the MAF, disconnect it and see if the engine runs better. If the engine runs better its the likely culprit. It would then be necessary to replace the MAF and its relays.
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Re: bad idle when hot (jennykayes84vette)
being a 90 i've got no codes and have a factory MAP sensor. fuel mileage isn't that high but its about 22-23 on the highway so its not far off