Low boost problem. help.
02-09-2013, 07:30 PM
#17
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that guy contacted me.
im pretty sure im gna do the tune but as far as the low boost problem, im kinda thinking its more of a mechanical issue (wastegate actuator problem) or maybe some kinda leak?
im pretty sure im gna do the tune but as far as the low boost problem, im kinda thinking its more of a mechanical issue (wastegate actuator problem) or maybe some kinda leak?
02-09-2013, 10:03 PM
#18
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geeze if you guys are that paranoid over a dp or a bov without a tune i can't fathom how you drive a modded car at all. just don't go and do excessive 3rd gear pulls if you wanna be safe but you're fine to drive around with those mods. your real issue is finding the boost problem. getting on the dyno is just going to be a waste of time if you have a leak or other mechanical issue. find and fix the problem before you face the embarrassment of getting pulled off the dyno. check for leaks and other possible parts before you try to get it tuned. pull a log and see what is really happening. there's probably a few people who would let you borrow a cable or help you pull a few logs. if it ran fine before then only recently started having issues it's not because you don't have a tune. just do your research and be careful who's advise you take on the internet, including mine. GL
02-09-2013, 10:07 PM
#19
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as Ryan mentioned...I would change out your HKS with a stock bypass valve...it's a strange issue how you sometimes get 10psi then boost normal...
I would highly recommend the PDX tune by Jarrad...he's really trying to keep the prices down...I think around $380 including the 1hr dyno time...
check out the PDXTune thread that Ojichan STI started...March 1-3.
Anyhow...change out your HKS and see what happens...
I would highly recommend the PDX tune by Jarrad...he's really trying to keep the prices down...I think around $380 including the 1hr dyno time...
check out the PDXTune thread that Ojichan STI started...March 1-3.
Anyhow...change out your HKS and see what happens...
02-10-2013, 12:27 AM
#20
geeze if you guys are that paranoid over a dp or a bov without a tune i can't fathom how you drive a modded car at all. just don't go and do excessive 3rd gear pulls if you wanna be safe but you're fine to drive around with those mods. your real issue is finding the boost problem. getting on the dyno is just going to be a waste of time if you have a leak or other mechanical issue. find and fix the problem before you face the embarrassment of getting pulled off the dyno. check for leaks and other possible parts before you try to get it tuned. pull a log and see what is really happening. there's probably a few people who would let you borrow a cable or help you pull a few logs. if it ran fine before then only recently started having issues it's not because you don't have a tune. just do your research and be careful who's advise you take on the internet, including mine. GL
02-10-2013, 12:53 AM
#21
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geeze if you guys are that paranoid over a dp or a bov without a tune i can't fathom how you drive a modded car at all. just don't go and do excessive 3rd gear pulls if you wanna be safe but you're fine to drive around with those mods. your real issue is finding the boost problem. getting on the dyno is just going to be a waste of time if you have a leak or other mechanical issue. find and fix the problem before you face the embarrassment of getting pulled off the dyno. check for leaks and other possible parts before you try to get it tuned. pull a log and see what is really happening. there's probably a few people who would let you borrow a cable or help you pull a few logs. if it ran fine before then only recently started having issues it's not because you don't have a tune. just do your research and be careful who's advise you take on the internet, including mine. GL
yeahh idk, thats what i figured. but i pulled some logs on my snap-on ethos, what i found was 170kpa at 6900 rpm 2nd gear pull which equals to 24psi but i know in actuality boosting about 18 id say but on my gauge it reads 11-12psi. and at idle or cruising speeds reading 27kpa (4psi). but my gauge reads 22inHg.
what i was thinking was the BCS. or the gauge.
02-10-2013, 01:56 AM
#22
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The reading from the ECU will always be higher because the sensor takes into account atmospheric pressure not the difference between atmospheric and the psi you are running.
Coming from experience with BOV's... our cars simply don't like them. I don't have any empirical evidence to prove otherwise.
Put a stock bpv on, reset your ECU by disconnecting the negative terminal on your battery and then holding the break pedal down for 30 seconds. Connect the battery again and see how she runs. Worst case scenario it runs worse and you put the bov back on, best case scenario you fix your boost problems.
Either way, its gotta a VAC leak somewhere. If you were constantly running low boost I could see the ECU learned something funky and is keeping you there(which is what would happen if you had a leak pre-turbo, but this can't be ruled out without taking everything apart to check it), but since its intermittent it sounds like something getting knocked around in the engine bay is randomly causing the vac to fluctuate.
Trace all VAC lines - BPV, Wastegate actuator, BCS, Intake manifold, and boost guage - make sure all hoses are supple and not hard or cracking, make sure all connectors are not brittle and that the hose around the barbed connector is not ripped or cracking.
Coming from experience with BOV's... our cars simply don't like them. I don't have any empirical evidence to prove otherwise.
Put a stock bpv on, reset your ECU by disconnecting the negative terminal on your battery and then holding the break pedal down for 30 seconds. Connect the battery again and see how she runs. Worst case scenario it runs worse and you put the bov back on, best case scenario you fix your boost problems.
Either way, its gotta a VAC leak somewhere. If you were constantly running low boost I could see the ECU learned something funky and is keeping you there(which is what would happen if you had a leak pre-turbo, but this can't be ruled out without taking everything apart to check it), but since its intermittent it sounds like something getting knocked around in the engine bay is randomly causing the vac to fluctuate.
Trace all VAC lines - BPV, Wastegate actuator, BCS, Intake manifold, and boost guage - make sure all hoses are supple and not hard or cracking, make sure all connectors are not brittle and that the hose around the barbed connector is not ripped or cracking.
02-10-2013, 10:45 AM
#24
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The reading from the ECU will always be higher because the sensor takes into account atmospheric pressure not the difference between atmospheric and the psi you are running.
Coming from experience with BOV's... our cars simply don't like them. I don't have any empirical evidence to prove otherwise.
Put a stock bpv on, reset your ECU by disconnecting the negative terminal on your battery and then holding the break pedal down for 30 seconds. Connect the battery again and see how she runs. Worst case scenario it runs worse and you put the bov back on, best case scenario you fix your boost problems.
Either way, its gotta a VAC leak somewhere. If you were constantly running low boost I could see the ECU learned something funky and is keeping you there(which is what would happen if you had a leak pre-turbo, but this can't be ruled out without taking everything apart to check it), but since its intermittent it sounds like something getting knocked around in the engine bay is randomly causing the vac to fluctuate.
Trace all VAC lines - BPV, Wastegate actuator, BCS, Intake manifold, and boost guage - make sure all hoses are supple and not hard or cracking, make sure all connectors are not brittle and that the hose around the barbed connector is not ripped or cracking.
Coming from experience with BOV's... our cars simply don't like them. I don't have any empirical evidence to prove otherwise.
Put a stock bpv on, reset your ECU by disconnecting the negative terminal on your battery and then holding the break pedal down for 30 seconds. Connect the battery again and see how she runs. Worst case scenario it runs worse and you put the bov back on, best case scenario you fix your boost problems.
Either way, its gotta a VAC leak somewhere. If you were constantly running low boost I could see the ECU learned something funky and is keeping you there(which is what would happen if you had a leak pre-turbo, but this can't be ruled out without taking everything apart to check it), but since its intermittent it sounds like something getting knocked around in the engine bay is randomly causing the vac to fluctuate.
Trace all VAC lines - BPV, Wastegate actuator, BCS, Intake manifold, and boost guage - make sure all hoses are supple and not hard or cracking, make sure all connectors are not brittle and that the hose around the barbed connector is not ripped or cracking.
and if anyone has a stock bpv on the side and is willing to let me try it out id appreciate it much.
02-10-2013, 10:45 AM
#25
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02-10-2013, 09:59 PM
#26
Are you sure that you are on a stock rom or is that downpipe catted? Are you running an o2 simulator?
A catless downpipe will trip a CEL without a simulator unless the code was disabled from a reflash. If you don't have a simulator it means your ROM is not factory.
What gear are you in when it hits only 10 psi? I would do a boost leak test first. Then check for an 02 simulator. If you don't have one ask someone to pull your rom.
I'm assuming this is a catless dp.
If you want to keep your psh psh bov, get an AP and ask Jarrad to put you on a speed density tune. He'll probably tell you it's not necessary but then you can tell him "but so is my bov" I'm jk
Moving to speed density will allow you to keep your bov and maybe get a tad bit of a response increase but nothing that would show up on a dyno.
A catless downpipe will trip a CEL without a simulator unless the code was disabled from a reflash. If you don't have a simulator it means your ROM is not factory.
What gear are you in when it hits only 10 psi? I would do a boost leak test first. Then check for an 02 simulator. If you don't have one ask someone to pull your rom.
I'm assuming this is a catless dp.
If you want to keep your psh psh bov, get an AP and ask Jarrad to put you on a speed density tune. He'll probably tell you it's not necessary but then you can tell him "but so is my bov" I'm jk
Moving to speed density will allow you to keep your bov and maybe get a tad bit of a response increase but nothing that would show up on a dyno.
02-10-2013, 11:31 PM
#27
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Are you sure that you are on a stock rom or is that downpipe catted? Are you running an o2 simulator?
A catless downpipe will trip a CEL without a simulator unless the code was disabled from a reflash. If you don't have a simulator it means your ROM is not factory.
What gear are you in when it hits only 10 psi? I would do a boost leak test first. Then check for an 02 simulator. If you don't have one ask someone to pull your rom.
I'm assuming this is a catless dp.
If you want to keep your psh psh bov, get an AP and ask Jarrad to put you on a speed density tune. He'll probably tell you it's not necessary but then you can tell him "but so is my bov" I'm jk
Moving to speed density will allow you to keep your bov and maybe get a tad bit of a response increase but nothing that would show up on a dyno.
A catless downpipe will trip a CEL without a simulator unless the code was disabled from a reflash. If you don't have a simulator it means your ROM is not factory.
What gear are you in when it hits only 10 psi? I would do a boost leak test first. Then check for an 02 simulator. If you don't have one ask someone to pull your rom.
I'm assuming this is a catless dp.
If you want to keep your psh psh bov, get an AP and ask Jarrad to put you on a speed density tune. He'll probably tell you it's not necessary but then you can tell him "but so is my bov" I'm jk
Moving to speed density will allow you to keep your bov and maybe get a tad bit of a response increase but nothing that would show up on a dyno.
but how can i tell?
who can i get to pull my rom?
and if it is simulated can i still get a tune?
but im replacing my POS Bov with a fully recirc. bov tomorrow. i havent gotten a chance to do a leak test yet, but changing my bov to fully recirc. is one thing im thinking could fix the prob, if not, then i wanted to change it out anyways.
the first time it acted up it was in a 3rd gear pull on a slight hill, i didnt feel a pull and looked at my gauge it read 10psi. and now lately its been that way constantly. sometimes i notice that if i let off the throttle a little while boosting my bov stays open for a long period. is that normal?
