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Out of ideas, boost problems.
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08-10-2019, 02:07 AM | #1 |
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Out of ideas, boost problems.
Hey guys i have been having problems with this car since i bought it a year ago and am completely out of ideas and frustrated. If anyone has any ideas i would be so grateful.
The car has had under target boost jerky throttle and timing corrections. Also had all of this with stock MAP. What i have checked is: NO active codes, NO boost leaks, new boost solenoid, new DV, and checked vacuum line with vac pump. Boost will peak to 15 then drop right away then around 5k rpm peak to 15 again. I have posted on take a look at my log thread but they said it was weird and didn't know what was going on. Running MHD stage 1 with 92 oct gas. Here is a couple logs with 92 oct plus octane booster https://datazap.me/u/erzenble/95-oct...11&tmax=100.50 https://datazap.me/u/erzenble/92-oct...30&tmax=182.17 Log in 4th gear WOT with really high corrections. 92 oct w booster https://datazap.me/u/erzenble/92-oct...20&tmax=200.77 |
08-11-2019, 10:52 AM | #3 |
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So you overboost a little on spool up then it corrects too much and eventually recovers. You are not going over the load limit/request and not getting throttle closures. I'm guessing you know this also happens on the stock tube because of feel rather than having a lot?
First steps are simple maintenance, when was the last time you replaced spark plugs or coils? Have you inspected any of the plugs to see if any look different (white or black in comparison to others). You replaced the boost solenoid, but did you replace the vacuum line down to the wastegate? The 4th gear log has corrections on all cylinders. Stop doing that unless you want to blow your engine. |
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08-11-2019, 08:13 PM | #4 | |
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Quote:
I put my vacuum pump on the line from the solenoid to check the wastegate moves ok and it held vacuum . Is that a good enough test or should I just replace the line? Also i was thinking about checking how much vacuum I'm making at idle. Do you happen to know what it should be at idle on an n55? Those corrections im not sure what to do about though. Could it be spark blowout? I'm at stock .028 gap but ive read people will run that on stage 1 just fine. I added octane booster and still am getting horrible corrections. |
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08-11-2019, 09:43 PM | #5 |
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So I just watched my wastegate while a friend started the car and it moved in slightly right away then went back out to where it was before we started it.
I had him blip the throttle a few times and it would move in about half the time. Isnt the wastegate supposed to be closed at idle? |
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