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Discussion Starter #1
Right before the turbo needle goes into the red zone she feels like rubber hits the washboard.
It happens at any speed. Opinions?
 

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That's a new saying. Is it misfiring?
 

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Discussion Starter #3
No codes no lights, original coils. Otherwise, she drives nice and smooth and accelerates as normal as long as I do not try to red zone it. The fuel pump is less than 10K since was replaced.
 

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Idk what you are trying to describe here. Is it dropping boost suddenly when it reaches the red part?
 

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You have non working wstegate and Trionic goes to safety mode and drops all off.
 

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Discussion Starter #7
The best I can describe is - it feels like vibration as you driving over the washboard and turbo can't go into the red zone. After I let the accelerator pedal off she is back to normal.
 

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misfiring
 

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It will if you keep on the pedal. When were plugs last replaced?
 

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Discussion Starter #11
It will if you keep on the pedal. When were plugs last replaced?
The car was sitting for a longer time prior to this happening. Plugs have probably 15K on them. Not more.
Is this what people describe as turbo stuttering?
 

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Yes. I would buy a coil and swap it down the line until it stops misfiring. Usually its only 1 that goes. Yes, often more go later but this is the cheapest way to troubleshoot coils vs buying 4 at once.

 

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Discussion Starter #13
Yes. I would buy a coil and swap it down the line until it stops misfiring. Usually its only 1 that goes. Yes, often more go later but this is the cheapest way to troubleshoot coils vs buying 4 at once.

Luckily I have 4 spare genuine coils I took from a salvaged newer car a while ago. Is there no way to 100% diagnose a bad one? Only try and error method? What about that electrical thingy that sits on top of the turbo, some kind valve. Could that cause the same symptoms if it is malfunctioning? Thanks!
 

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Luckily I have 4 spare genuine coils I took from a salvaged newer car a while ago. Is there no way to 100% diagnose a bad one? Only try and error method? What about that electrical thingy that sits on top of the turbo, some kind valve. Could that cause the same symptoms if it is malfunctioning? Thanks!
You'll need a scan tool that can read Mode 6 data. You may be misfiring, but just not at a threshold to set a MIL light command. Also, since you state that the issue occurs during acceleration, I would suspect a coil is breaking down. Would need to see the waveform on a PicoScope to see the current ramp pattern to know for sure. If you can pinpoint which cylinder is misfiring, you could play swap-tronics. Let's say #1 is your issue. Swap the coil on cylinder #1 with cylinder #2. Swap the plug in cylinder #1 with cylinder #3. Does the misfire move?
 

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Luckily I have 4 spare genuine coils I took from a salvaged newer car a while ago. Is there no way to 100% diagnose a bad one? Only try and error method? What about that electrical thingy that sits on top of the turbo, some kind valve. Could that cause the same symptoms if it is malfunctioning? Thanks!
Perfect. Grab one and swap down the line. Shouldn't take very long to pinpoint the bad one.
 

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Discussion Starter #17
To report back, plugs have been cleaned, degreased and re gaped to 0.9 mm, all four coils replaced and she is back to normal. Turbo is screaming like brand new and all the way in the red. She brings a smile to my face again.

Thanks to all who contributed!
 
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