TD04 wastegate issues
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Car Info: 04 psm wrx sedan
Gas was a thought as it first happened when gas was really low...I've put chevron and shell in (about half tank each) with no change it seems...car has stage 1 acn91 tune
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We could always unmarry your AP from your car. Hook it to mine or someone else's... see if it does it to their car. If it does then it's the tune or the AP. If not... it's mechanical.
I'd be happy to let you test my car but my turbo is doodoo so until I fix it I'm not gonna be much help.
I'd be happy to let you test my car but my turbo is doodoo so until I fix it I'm not gonna be much help.
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Brian have you tried checking your wastegate lines for cracks?
Try bypassing your MBC or EBC and just go off straight wastegate pressure, then log your car and see If you hit 12-14#.
If not I would have a leak down / compression test done, Your IAM should not be bouncing around that much.
Id also pressure test your Intake system Pre and Post turbo.
Try bypassing your MBC or EBC and just go off straight wastegate pressure, then log your car and see If you hit 12-14#.
If not I would have a leak down / compression test done, Your IAM should not be bouncing around that much.
Id also pressure test your Intake system Pre and Post turbo.
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Brian have you tried checking your wastegate lines for cracks?
Try bypassing your MBC or EBC and just go off straight wastegate pressure, then log your car and see If you hit 12-14#.
If not I would have a leak down / compression test done, Your IAM should not be bouncing around that much.
Id also pressure test your Intake system Pre and Post turbo.
Try bypassing your MBC or EBC and just go off straight wastegate pressure, then log your car and see If you hit 12-14#.
If not I would have a leak down / compression test done, Your IAM should not be bouncing around that much.
Id also pressure test your Intake system Pre and Post turbo.
Did this start after filling up the tank? If so it's likely the gas. If not, I would check for lose parts possibly causing noise setting off the knock sensor. Finally get the car logged and verify that A/F is in a safe range.
-- Ed
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It doesn't sound like a boost leak. The ECU is just turning off boost control because the IAM is dropping from knock.
Did this start after filling up the tank? If so it's likely the gas. If not, I would check for lose parts possibly causing noise setting off the knock sensor. Finally get the car logged and verify that A/F is in a safe range.
-- Ed
Did this start after filling up the tank? If so it's likely the gas. If not, I would check for lose parts possibly causing noise setting off the knock sensor. Finally get the car logged and verify that A/F is in a safe range.
-- Ed
whats a safe a/f for stage 1 cobb map?
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Did this start after adding or removing any parts or working on the car at all or just out of the blue? Was everything running well for an extended period of time since your engine was built before this started happening? Was the tune ever checked and verified to be running safely after the build?
-- Ed
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Thread Starter
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Car Info: 04 psm wrx sedan
They usually run 10.3-10.8 under full boost. You will need a wideband to verify this as the stock O2 sensor can only read to about 11.4:1.
Did this start after adding or removing any parts or working on the car at all or just out of the blue? Was everything running well for an extended period of time since your engine was built before this started happening? Was the tune ever checked and verified to be running safely after the build?
-- Ed
Did this start after adding or removing any parts or working on the car at all or just out of the blue? Was everything running well for an extended period of time since your engine was built before this started happening? Was the tune ever checked and verified to be running safely after the build?
-- Ed
just filled up new gas today and reset ecu once more (DAM started at 12)...did a 2-3 pull onto freeway and my DAM stayed at 12, got into 5th and tried to recreate symptoms and the DAM went to 16-14-15 all within a few seconds and its stayed at 15 even after a few more pulls
boost max 10psi in 2nd gear though
need to do a boost leak test
previously known as wrxBRAH
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it came out of the blue, motor has ~12k, nothing has been changed since oil change 1500miles ago....tune was just loaded but not verified and been running with it 15k on last motor (got rod knock from torn turbo inlet/bad a/f) and now another 12k on this one
just filled up new gas today and reset ecu once more (DAM started at 12)...did a 2-3 pull onto freeway and my DAM stayed at 12, got into 5th and tried to recreate symptoms and the DAM went to 16-14-15 all within a few seconds and its stayed at 15 even after a few more pulls
boost max 10psi in 2nd gear though
need to do a boost leak test
just filled up new gas today and reset ecu once more (DAM started at 12)...did a 2-3 pull onto freeway and my DAM stayed at 12, got into 5th and tried to recreate symptoms and the DAM went to 16-14-15 all within a few seconds and its stayed at 15 even after a few more pulls
boost max 10psi in 2nd gear though
need to do a boost leak test
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Drove again today...car was fine for 10or so miles of city driving...DAM stayed at 15...got on freeway and in 5th gear I saw it dip to 12-8 at around 3k rpm
Downshifted to 4th and did a quick pull and the DAM went back up to 12 and now its staying at 11
So 5th gear, 3K rpm is where the DAM falls
I'm so confused haha
Downshifted to 4th and did a quick pull and the DAM went back up to 12 and now its staying at 11
So 5th gear, 3K rpm is where the DAM falls
I'm so confused haha
previously known as wrxBRAH
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From: San Jose / Campbell
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Drove again today...car was fine for 10or so miles of city driving...DAM stayed at 15...got on freeway and in 5th gear I saw it dip to 12-8 at around 3k rpm
Downshifted to 4th and did a quick pull and the DAM went back up to 12 and now its staying at 11
So 5th gear, 3K rpm is where the DAM falls
I'm so confused haha
Downshifted to 4th and did a quick pull and the DAM went back up to 12 and now its staying at 11
So 5th gear, 3K rpm is where the DAM falls
I'm so confused haha



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