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Discussion Starter #1
I'm getting hella weird idle issues where after driving, if I push the clutch and go to N, the RPMs drop to 900, bounce up to 2k-1.5k then settle at 1500 until I stop physically moving. Also when I kick the AC on, RPMs go crazy for a few seconds then settle at 900.

This has been a constant issue where it does this same thing every time. Sometimes bouncing 2-3 times before settling at 1500 until stopped.

So far I've checked for vacuum leaks. Sprayed the whole engine down and found nothing. My AP is reading -9.7PSI along with my vacuum guage reading 20.5InMg. So that's perfect. I ran a compression test and all cylinders were at 180PSI give or take 5 from each other.

The car is bone stock except K&N drop in filter and an AP. The issue started when I installed the AP and the ECU got reset. I have tried all the Cobb OTS tunes, my speed circuit OTS tune, and factory tune with the AP uninstalled. All do the same exact thing. I've seen post and videos online of this exact issue, but no solutions.

What I'm going to try next is:
Swap fuel relay
Clean MAF
Clean TB
Change spark plugs

Though I have some serious doubts this will actually fix anything. So does anyone know what's up with this car? It's running perfect otherwise. No loss of power and I'm hitting target boost.
 

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How long has it been since you did the AP?

I remember back on my 08 X that the car would have to "re-learn" things after the AP was installed or flashed something. It wiped out certain parameters and would run kind of funny for a little while before it got everything straightened back out.
 

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Discussion Starter #4
How long has it been since you did the AP?

I remember back on my 08 X that the car would have to "re-learn" things after the AP was installed or flashed something. It wiped out certain parameters and would run kind of funny for a little while before it got everything straightened back out.
It hasn't been more than a week with 1 map on it before I've flashed a new one or different one. I know there's a learning time, but it shouldn't be doing this idle bounce for 3 days.
 

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Discussion Starter #5
It hasn't been more than a week with 1 map on it before I've flashed a new one or different one. I know there's a learning time, but it shouldn't be doing this idle bounce for 3 days.
+1
Thanks for +1and adding to the convo to get your post number up.


Anyway, I swapped the fuel pump relay, cleaned the MAF, cleaned the TB, and disconnected the batter for am hour. Issue got worse.

However, yesterday when I was driving around hard, I noticed that at about 6-7k RPMs, I heard a rattling sound. Sounded like a heat shield vibration. I took the intake off and looked at the compressor wheel and saw scoring around the body. I moved the shaft and it has some up and down play, maybe 2-3mm of movement. From the looks of it, it's touching the housing and causing the scoring and noise.
 

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This happened to me two weeks ago but it happened when I swapped out my HIDs for LEDs. Disconnected the battery and did the swap.
Later that day I was driving on the highway and traffic was coming to a stop. Was in 5th and then depressed the clutch and went in to neutral. RPMs started bouncing between 800-1500k.
Didn't stop until I went to a complete full stop. Issue did not happen when idle but was able to reproduce when i started driving again and went to neutral.
Happened for two days then hasn't happened since. 2015 X GSR. FBO, Tuned.
 

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Discussion Starter #7
This happened to me two weeks ago but it happened when I swapped out my HIDs for LEDs. Disconnected the battery and did the swap.
Later that day I was driving on the highway and traffic was coming to a stop. Was in 5th and then depressed the clutch and went in to neutral. RPMs started bouncing between 800-1500k.
Didn't stop until I went to a complete full stop. Issue did not happen when idle but was able to reproduce when i started driving again and went to neutral.
Happened for two days then hasn't happened since. 2015 X GSR. FBO, Tuned.
Yea this is exactly what it's doing. I disconnected my battery yesterday and it seems like it's sorting its self out, but I still think there is something wrong and the ECU is just correcting itself.

I still gotta do a boost leak test and change spark plugs.
 

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Discussion Starter #12
I am having the same issuee too, can't figure it out too. Did you swap your Relay ?
Yea. I've tried new MAPS, cleaned TB, cleaned MAF, disconnected battery, vacuum leak test, and upgraded fuel relay. None of that helped. The thing I need to do next is spark plugs, boost leak test, and replace turbo (mine has shaft play).
 

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if your turbo is toasted it could cause strange idle issues, if its going between spinning and not spinning or spinning slower than it should it could cause air flow issues. also, if the compressor wheel is rubbing you should definitely park it before you send any more aluminum shavings into your cylinders....
 

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Discussion Starter #14
if your turbo is toasted it could cause strange idle issues, if its going between spinning and not spinning or spinning slower than it should it could cause air flow issues. also, if the compressor wheel is rubbing you should definitely park it before you send any more aluminum shavings into your cylinders....
That's the strange bit. Just sitting idle, it's fine. Idles normally. Only when moving does it do the bounce to 1500. Either way, I bought a new-used turbo, so I'm gonna replace it and see what happens. Dealership has the car atm for other unrelated issues. If the replacement turbo and boost leak test don't come back with any results, I'm lost at this point and will have to bring it in for something.
 

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Discussion Starter #15
replaced spark plugs and nothing. did a BLT and found out that my stock BOV is not holding any sort of pressure. pumped up to 10 PSI and it would not hold it even for a few seconds. so i ordered a Cobb LF BPV and we shall see if that fixes the issue. got my fingers crossed! if not, well i was gonna upgrade it anyway.
 

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I would say that this is probably your issue if metered air is bleeding and not going to the engine that would cause a problem !
 

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Discussion Starter #18
I would say that this is probably your issue if metered air is bleeding and not going to the engine that would cause a problem !
Well it was leaking internally. Leaking back into the intake. But it was one bad leaky boi. Literally wouldn't even hold 5psi according to my guage. I'm hoping it's the issue. If not, turbo is is getting replaced anyway. So maybe that is. That BOV was the only leaking part.
 
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