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Solved: No boost

Erbarry

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#1
Solved: So after checking just about everything, I posted on a FB group and someone said they had the same issue and their turbine wheel came apart without any warning. Simply taking off the downpipe seemed like a long process so I bought a used turbo and figured I might as well have one on hand if it is the turbo. Took the downpipe off and the turbine wheel was basically gone with chunks sitting in the housing and debris in the downpipe. I didn’t think it could be the turbo because there were never any signs of it going, the compressor side was fine, spun freely and had no play.


Yesterday while getting on the highway WOT the car simply lost power and noticed the car wasn’t boosting as if it was in limp mode, no misfire, no pop, no sign of anything just simply dropped all boost. No faults, checked all pipes and lines, nothing blew off. Boost solenoid and DV have connectors on them and sounds like the solenoid is moving when you power on the car. Pulled GFB Valve off and it moves freely but couldn’t figure out if you can get it to operate with power cycling. Hooked up all the vacuum lines to run off only wastegate pressure but still no luck. I took off the intake elbow coming off the turbo, wheel spins freely and there’s no shaft play. At first I thought something was wrong with the turbo because it wasn’t spinning while idling but after reading a bit that can be normal. Only thing left to do is a boost leak test. When the car goes into limp mode what causes it to not build boost? What else can I check? AP shows max PSI of around -0.4. I also made sure I didn’t switch map slots, reset ECU and re flashed map.
 


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Hypergram

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#2
The only possible thing I can think of is you may have put it in "economy mode" by accident. Some tunes allow you to control the mode you're in with the steering wheel controls so maybe you unknowingly pressed them?
 


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Erbarry

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The only possible thing I can think of is you may have put it in "economy mode" by accident. Some tunes allow you to control the mode you're in with the steering wheel controls so maybe you unknowingly pressed them?
Forgot to mention that I did check to make sure I was in slot 1, also reset ECU and eventually reflashed tune.
 


TyphoonFiST

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#4
Any codes set in the Computer memory? just because there is no check engine light doesn't mean there isn't any stored!
 


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Erbarry

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Any codes set in the Computer memory? just because there is no check engine light doesn't mean there isn't any stored!
I did not check the memory, forgot that the AP doesn’t show stored codes. I’ll check them tonight.
 


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Erbarry

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So the only stored code I have is P061A ECM Engine torque-performance problem. Fuse #24 is good but in the manual it says it’s for ignition coil, I checked the rest in the Engine fuse box and all of them were good. I did a boost leak check and it’s holding pressure just fine.
 


TyphoonFiST

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#9
Uninstall the tune and re-install it then do a Kam reset with the Ap3. Then it will have to re-learn itself.

Sent from my SM-N950U1 using Tapatalk
 


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Erbarry

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Thread Starter #10
Is it possibe the WG is stuck open?
Thought the same thing but it wouldn’t have held pressure with the leak test.


Uninstall the tune and re-install it then do a Kam reset with the Ap3. Then it will have to re-learn itself.

Sent from my SM-N950U1 using Tapatalk
I did that a few days ago, nothing has changed since. It’s acting like I’ve gone in limp mode. I’d like to know what stays open when the car goes into limp mode but havent found it yet.
 




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