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Discussion Starter #1
I had never seen this before in a drive by wire throttle body vehicle, but after a while of driving and putting my car on neutral or park my rpm will hang around 1000 rpm. This also happens when I WOT and come to a stop. When in gear, it also seems high probably around 800 rpm. I shut the car off and idles fine again once I restart. I have also managed to bring the rpm down by turning the steering wheel full lock, which I guess adds load to the motor, but sometimes it will go back up.

Think I have a bad throttle body?
I have cleaned it with same results...
 

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Check engineering mode for throttle % when at idle. I'd have to look at mine to see what seems right.
 

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Discussion Starter #3
Check engineering mode for throttle % when at idle. I'd have to look at mine to see what seems right.
Actually did that yesterday, it was behaving like it needs to and was at 5% throttle. Need to check what percentage it is when it misbehaves...i did get a CEL for throttle code
 

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Discussion Starter #4
so this is how the throttle position looks like.
6.6% after warm up, this is before driving off and doing my thing.
5.4% and 5.8% after driving for about an hour with no WOT.
check engine light went away on its own.
it has done this a couple of times now, never did it before the DOD delete and im thinking that since i am running the LS3/LS7 style valley cover, i am getting too much oil into the throttle area.....i dont have a catch can. dont burn me too bad pls lol
 

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Which check engine code is showing for the throttle body? Has it been cleaned to remove foreign matter from around the blade mechanisms?
 

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Discussion Starter #6
Which check engine code is showing for the throttle body? Has it been cleaned to remove foreign matter from around the blade mechanisms?
I have cleaned it and checked for any obstructions, everything looks good. Code is P0507 Idle air control system RPM higher than expected. Seems to be doing it more now.
 

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Discussion Starter #7
Finally had time to drive it to work, i was able to pull the code and i snapped some pics of where it idles.
 

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Post a clear picture of you engine bay.

Your signature states that you have a tune using HP Tuners. Who tuned it? Can you post the tune?
 

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Discussion Starter #9
Post a clear picture of you engine bay.

Your signature states that you have a tune using HP Tuners. Who tuned it? Can you post the tune?
I paid a guy to tune out the DOD and he uploaded a tune via HPTuners...so i would need to ask him to send me the file. Honestly, the car pulls fine and drives ok, but after the tune the idle was a bit higher than normal and then 2 months later this code starting coming up. I am almost 90% sure that this is tune related. Even the transmission shift points are off and i think the tune he uploaded upped the pressure line on the tranny so it jerks every gears pretty bad. I will post a pic of the engine bay as soon as i am out of work. Meanwhile let me see if I can get the tune emailed to me
 

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I'm almost certain its tune related as well. Post the tune, someone on here could edit it for you and probably fix it.
 

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First thoughts are either a defective tune or vacuum leak. Tend to lean more towards the former and hopefully the email response aides in identifying the culprit.
 

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Discussion Starter #12
First thoughts are either a defective tune or vacuum leak. Tend to lean more towards the former and hopefully the email response aides in identifying the culprit.
Well. The guy that "tuned" it wont email me crap. Looks like im in the dark here, I'm just hopeing he didnt lock the tune. I can rule out the throttle body by removing my ls3 one from my camaro. Think that would work? I would pay the guy a visit but hes 2 hours out of my way.

The car worked fine till about a month or so ago when the rpm started going up on its own....any other suggestions?

Might just end up getting a proper dyno tune
 

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Discussion Starter #13
So I parked today and rpm was high so I reved to WOT once, didnt leave it there, just a quick rev and the rpms came back down to normal. I would think that a bad tune would still keep the rpms high right? I know the tune is **** but i would like to hold off 1 more month to get it properly tuned, need to knock off some debt first.
 

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Discussion Starter #15
Hopefully he comes through, its not like the guy uploaded a bulletproof tune lol. I will look into replacing the throttle body, might still be a good option for me down the road. Either way, i think a faulty TB might show up when it gets properly tuned. I got the car back up running after the DOD Delete on 11/13/2018. The rpm started change around mid January.
 

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Discussion Starter #16
alright, so I finally got the tune emailed to me.
how would i go about posting it up? since i dont have HPtuners idk if this file can be posted up as a link or something.
Help on this matter pls?!
 

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Just click on the "Reply" Button. And attach the tune using the "Attach" button
 

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Quick reply. Drag and Drop File Upload (drag files here to attach) or Quick reply. Go advanced. Manage attachments. Upload attachment
 

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Discussion Starter #19
i tried it but it wont attach it and when i download the tune so i can access the file from the documents it creates a link instead of a file. i uploaded a picture of the email
 

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Joepeinado
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