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Discussion Starter #1
Hello, newbie here. I’ve been on the forums searching for this issue but can’t find it. If there is something out there, my feelings won’t be hurt, please send link. Well here goes....when the air conditioning is off, the car purrs like a kitten, absolutely no issues! Idle is at 1000-1100. However once the a/c is running, when I come to a stop or have the car in neutral she has a very erratic idle and then shuts off. I’ve read not having heat shield for the intake could send hot air, while the a/c is running, in that area and throw the MAF for loops. So I bought a MAP Rev 2 heat shield to aid in this issue. Installed it, took it out for a drive and the EXACT same thing is happening again! Again if there is a link please send.

Thanks
 

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Discussion Starter #2
Would re-learning idle help or not. Anyone?
 

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Idle is at 1000-1100
Stock idle is in the 700-800 range. I'm going to strongly suspect a vacuum leak somewhere past the throttle body. Did you do any work before it started? The car will still run halfway decently with a vacuum line disconnected but will do funky things under light load (like the AC coming on or tip-in light throttle)
 

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Discussion Starter #6
Thanks. I’ll get on this.
 

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Discussion Starter #7
Update...Checked the lines and found only these two (or one) not connected. Did a compression check, nothing less than 162 on all 4. Haven’t done the throttle body clean yet. Being methodical is ok with me not in a big rush.
 

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Discussion Starter #8
Oh sorry I did clean the MAF. :imstupid:
 

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Discussion Starter #9
Same outcome.:slaphead:
 

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Discussion Starter #11

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hey i posted this here too (https://www.evoxforums.com/forums/showthread.php?t=401192)



I had the same issue a while back. turned out to be a dirty throttle body plate, in my case at least.

Apparently our cars adjust the throttle plate a little bit at idle, and when it gets dirty, the plate can kind of get stuck. It prevent the plate from making really small adjustments when it needs to such as at idle.

As soon as the shop i go to told me this, i wiped the throttle body with a rag, put it back together - and it solved the issue.

best of luck
 

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Discussion Starter #13
Thanks for the info. Will do this as well. :thumbup:
 

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Discussion Starter #14
hey i posted this here too (https://www.evoxforums.com/forums/showthread.php?t=401192)



I had the same issue a while back. turned out to be a dirty throttle body plate, in my case at least.

Apparently our cars adjust the throttle plate a little bit at idle, and when it gets dirty, the plate can kind of get stuck. It prevent the plate from making really small adjustments when it needs to such as at idle.

As soon as the shop i go to told me this, i wiped the throttle body with a rag, put it back together - and it solved the issue.

best of luck
Update: Cleaned the throttle body with CRC throttle body cleaner...fixed. Thank you for going through what you did it saved me so much time and headaches. Idling around 900-1000 with a/c on or off. Sorry to you fellas up north bout all the A/C talk. Keep safe up there.
 

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Discussion Starter #15
Update: Cleaned the throttle body with CRC throttle body cleaner...fixed. Thank you for going through what you did it saved me so much time and headaches. Idling around 900-1000 with a/c on or off. Sorry to you fellas up north bout all the A/C talk. Keep safe up there.
Oops. Thanks to xDMrFluffeexD who went through 6+ hours of wrenching. :duh:
 

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Discussion Starter #19
Welp only after 2 days...I lost boost and threw a p0171 code. I was going to work, had boost and halfway there bam no boost. I was down to almost an empty tank. Stop filled up and no boost. Came home re-checked the hose to the throttle body and it’s on tight. Checked all other hoses and connections...all tight. Cleaned MAF again also. Any thoughts?
 

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Discussion Starter #20
Sorry forgot to include....no white/black/blue smoke whatsoever. No oil leak. Idle is same as before.
 
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