turbo pressure bouncing

riderome · 11-01-2009, 05:36 AM

I took a drive up to the headless horseman's haunted house today and on the ride home I decided to just do a straight pull off the ramp onto the highway. Second gear my psi quickly hit 15 and then a split second after staying at a steady 15 pounds, it jumped up to 19 and then started bouncing between 19 and 10. Every gear is like this, not that the gear would matter.

Any ideas? I reset the ecu and it still occurred, cel did go on but is off now due to the reset.

* Registered users of the site do not see these ads.

bryan_johnson · 11-01-2009, 08:54 AM

Do you have any mods we should know about? Or is it bone stock?

riderome · 11-01-2009, 03:05 PM

Mods are basic bolt ons from the previous owner such as a Helix catless downpipe, HKS uppipe, HKS carbon ti exhaust, HKS ssqv bov, and a K&N short ram intake. The car has never been tuned or remapped whatsoever, still trying to find money to get a tune.
Any ideas at all?

riderome · 11-01-2009, 07:42 PM

I just cleaned the maf sensor and the maf tube with some maf sensor cleaner and the same problem is still there. I hit a steady 14.5-15psi and then after 3 seconds or so it jumps to 18 and then back down.

CKxx · 11-01-2009, 08:27 PM

I would start by replacing all the lines related to boost control with new ones. Take special care to use the same size line, as well as to remove the restrictor pill from the factory lines and re-use the factory "T".

In the mean time, do not keep doing that if it is going to boost levels higher than stock.

riderome · 11-01-2009, 08:38 PM

Ok I'll pick up some lines tomorrow and see if that does the trick, thanks for the response.

WhiteBgeye02 · 11-01-2009, 09:42 PM

i had this same problem prior to my opensource tune. with the diff dp the waste gate isnt used to .the extreme flow that a bellmouth dp has so it opens up and then it releases alot more than it was expecting so it slaps shut and it boosts way back up. so it opens again and looses too much pressure. its a theory my friend told me that knows ALOT about these cars. once i got a tune the pressure bouncing disappeared completly

CKxx · 11-01-2009, 11:24 PM

Quote:

Originally Posted by WhiteBgeye02

i had this same problem prior to my opensource tune. with the diff dp the waste gate isnt used to .the extreme flow that a bellmouth dp has so it opens up and then it releases alot more than it was expecting so it slaps shut and it boosts way back up. so it opens again and looses too much pressure. its a theory my friend told me that knows ALOT about these cars. once i got a tune the pressure bouncing disappeared completly

This is also possible, but he made it sound like it had worked fine for some period of time, then began to act up.

jsalassi · 11-01-2009, 11:46 PM

try cleaning out the boost control solenoid wth some rubbing alcohol.

riderome · 11-01-2009, 11:57 PM

Quote:

Originally Posted by CKxx

This is also possible, but he made it sound like it had worked fine for some period of time, then began to act up.

I had the car a little over 8 months now and the car ran 15-16 psi without problems. Lately the car has been having days were it feels very weak, even though the turbo pressure shows the same psi. I never had this psi bouncing issue up until last night. Then again the downpipe is massive and it is running on a stock map with no tune.

I took a look at all the hoses and noticed that the hose that connects the intake to the turbo had a loose clamp where it is supposed to be sitting on the center of the turbo spool. I began to tighten it and saw that it wasn't fully sitting on the turbo.

Could this mean that the MAF sensor is out of whack, due to the fact that air may be escaping under high pressure from where the clamp has slipped off? I couldn't get my giant hands to fit in and push the clamp back up there so my friend with the gti is going to try tomorrow.

BTW I checked out the mini boost control hoses connected with the T and they seem fine but I will replace them anyways.

spulbi · 11-02-2009, 01:51 AM

Your boost shouldn't be fluctuating like that even with all those mods and no tune. I would check for boost leaks.

+1 on checking the bcs

riderome · 11-02-2009, 05:38 PM

Found the definate problem, the turbo inlet hose is ripped to hell by the hose clamp, ordered a new oem one so should be here by wednesday.

spulbi · 11-02-2009, 06:06 PM

Quote:

Originally Posted by riderome

Found the definate problem, the turbo inlet hose is ripped to hell by the hose clamp, ordered a new oem one so should be here by wednesday.

Why didn't you go with a silicone inlet?

Anyways.. yeah that's a pretty huge boost leak.

WhiteBgeye02 · 11-02-2009, 06:17 PM

mine was also ripped very bad. got a cheapy on ebay. works great. a few guys around here are having great luck with them. if u canreturn it i would and buy a ebay one for like 80 bucks. glad u found the problem!

TeamJTC · 11-02-2009, 06:39 PM

I hope this is my problem!

riderome · 11-02-2009, 07:57 PM

my father is a shop foreman so he contacted a friend at a subaru dealer and got the oem hose and new clamps for $80, I was thinking of a Perrin silicone one but I hward they slip off at times and it is almost a massive $300! I'll let you all know how the car runs once I throw it on.

11-01-2009, 05:36 AM	#1
riderome Scooby Newbie Member#: 210603 Join Date: May 2009 Chapter/Region: Tri-State Location: Staten Island, New York Vehicle: 2002 WRX Silver	turbo pressure bouncing I took a drive up to the headless horseman's haunted house today and on the ride home I decided to just do a straight pull off the ramp onto the highway. Second gear my psi quickly hit 15 and then a split second after staying at a steady 15 pounds, it jumped up to 19 and then started bouncing between 19 and 10. Every gear is like this, not that the gear would matter. Any ideas? I reset the ecu and it still occurred, cel did go on but is off now due to the reset. * Registered users of the site do not see these ads.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

11-01-2009, 08:54 AM	#2
bryan_johnson Scooby Newbie Member#: 78987 Join Date: Jan 2005	Do you have any mods we should know about? Or is it bone stock?

11-01-2009, 03:05 PM	#3
riderome Scooby Newbie Member#: 210603 Join Date: May 2009 Chapter/Region: Tri-State Location: Staten Island, New York Vehicle: 2002 WRX Silver	Mods are basic bolt ons from the previous owner such as a Helix catless downpipe, HKS uppipe, HKS carbon ti exhaust, HKS ssqv bov, and a K&N short ram intake. The car has never been tuned or remapped whatsoever, still trying to find money to get a tune. Any ideas at all?

11-01-2009, 07:42 PM	#4
riderome Scooby Newbie Member#: 210603 Join Date: May 2009 Chapter/Region: Tri-State Location: Staten Island, New York Vehicle: 2002 WRX Silver	I just cleaned the maf sensor and the maf tube with some maf sensor cleaner and the same problem is still there. I hit a steady 14.5-15psi and then after 3 seconds or so it jumps to 18 and then back down.

11-01-2009, 08:27 PM	#5
CKxx Scooby Specialist Member#: 33458 Join Date: Feb 2003 Chapter/Region: Tri-State Location: West Chester, PA Vehicle: 1988 Justy 1.2L 4WD 2002 WRX 2.1L AWD	I would start by replacing all the lines related to boost control with new ones. Take special care to use the same size line, as well as to remove the restrictor pill from the factory lines and re-use the factory "T". In the mean time, do not keep doing that if it is going to boost levels higher than stock.

11-01-2009, 08:38 PM	#6
riderome Scooby Newbie Member#: 210603 Join Date: May 2009 Chapter/Region: Tri-State Location: Staten Island, New York Vehicle: 2002 WRX Silver	Ok I'll pick up some lines tomorrow and see if that does the trick, thanks for the response.

11-01-2009, 09:42 PM	#7
WhiteBgeye02 Scooby Newbie Member#: 224785 Join Date: Sep 2009 Chapter/Region: MWSOC Location: neenah Vehicle: 2002 wrx aspen white!	i had this same problem prior to my opensource tune. with the diff dp the waste gate isnt used to .the extreme flow that a bellmouth dp has so it opens up and then it releases alot more than it was expecting so it slaps shut and it boosts way back up. so it opens again and looses too much pressure. its a theory my friend told me that knows ALOT about these cars. once i got a tune the pressure bouncing disappeared completly

11-01-2009, 11:46 PM	#9
jsalassi Scooby Specialist Member#: 61261 Join Date: May 2004 Chapter/Region: TXIC Location: E-uless Vehicle: 04 WRX Wagon Wingless+Blue+Stg2	try cleaning out the boost control solenoid wth some rubbing alcohol.

11-02-2009, 01:51 AM	#11
spulbi Scooby Specialist Member#: 190378 Join Date: Sep 2008 Chapter/Region: NWIC Location: Vancouver/Portland area Vehicle: 2002 WRX stg2 w/ 2005 STI front conver	Your boost shouldn't be fluctuating like that even with all those mods and no tune. I would check for boost leaks. +1 on checking the bcs

11-02-2009, 05:38 PM	#12
riderome Scooby Newbie Member#: 210603 Join Date: May 2009 Chapter/Region: Tri-State Location: Staten Island, New York Vehicle: 2002 WRX Silver	Found the definate problem, the turbo inlet hose is ripped to hell by the hose clamp, ordered a new oem one so should be here by wednesday.

11-02-2009, 06:17 PM	#14
WhiteBgeye02 Scooby Newbie Member#: 224785 Join Date: Sep 2009 Chapter/Region: MWSOC Location: neenah Vehicle: 2002 wrx aspen white!	mine was also ripped very bad. got a cheapy on ebay. works great. a few guys around here are having great luck with them. if u canreturn it i would and buy a ebay one for like 80 bucks. glad u found the problem!

11-02-2009, 06:39 PM	#15
TeamJTC Scooby Newbie Member#: 224475 Join Date: Sep 2009	I hope this is my problem!

11-02-2009, 07:57 PM	#16
riderome Scooby Newbie Member#: 210603 Join Date: May 2009 Chapter/Region: Tri-State Location: Staten Island, New York Vehicle: 2002 WRX Silver	my father is a shop foreman so he contacted a friend at a subaru dealer and got the oem hose and new clamps for $80, I was thinking of a Perrin silicone one but I hward they slip off at times and it is almost a massive $300! I'll let you all know how the car runs once I throw it on.