low boost psi, wtf

supradad86_5 · 06-04-2007, 05:18 AM

Alright first, I had the boost set to 13psi, it was boosting fine, every now and then I would get a little hesitation from it, thinking that I am lacking on the fuel end of things, although still not hitting fuel cut. One day it just didnt wanna boost up to 13psi anymore, it seems to stay around 8-10psi now when I hit full boost. I swear its like the car has a mind of its own and gets an attitude with me at times. Well I have checked all of the intake piping for leaks and found nothing. I have even taken the vaccum line off of my manual boost controller and ran it like that, in this case it should run up to about 15psi and hit fuel cut, which it didnt, it stayed around 8-10psi, but it did pull pretty hard. I kinda think that I might be having problems with the gauge having a leak in the line or something and only getting about 10 psi to it. I really couldn't tell from the run I did without the line on. I think that it should have hit fuel cut with the line off, if it boosted up to 15psi, and it didnt. Has anyone had problems with the turbo only holding a lower boost than normal? Maybe going out or something? Or are there any other suggestions? Thanks a lot!

ddmcse · 06-04-2007, 02:19 PM

it's always been a loose hose for me

supradad86_5 · 06-05-2007, 03:35 AM

So this morning it boosted up to 13psi when the engine was still kinda cool, then after running for about 15 min it would only boost to 8psi. I rechecked all of the vac. hoses and intake piping, everything is tight and in it its place. I did run it again this evening without the wastgate acuator hooked up and it still boosted up to 8psi, so I am getting to the point that I think I can rule out the aftermarket gauge because if it did boost all the way up it would have hit fuel cut which it didnt. Any other ideas, anything would be helpful at this point.

turbo 352 · 02-09-2014, 01:39 AM

Quote:

Originally Posted by supradad86_5

So this morning it boosted up to 13psi when the engine was still kinda cool, then after running for about 15 min it would only boost to 8psi. I rechecked all of the vac. hoses and intake piping, everything is tight and in it its place. I did run it again this evening without the wastgate acuator hooked up and it still boosted up to 8psi, so I am getting to the point that I think I can rule out the aftermarket gauge because if it did boost all the way up it would have hit fuel cut which it didnt. Any other ideas, anything would be helpful at this point.

Check your oil pressure sounds like your losing pressure after warm up.

supradad86_5 · 02-09-2014, 02:05 AM

This was a hose issue back in 2007, back when I still had a Supra. Thanks for the input though.

06-04-2007, 05:18 AM	#1
supradad86_5 Stock Join Date: Apr 2007 Location: Bonney Lake, Wa Posts: 20	low boost psi, wtf Alright first, I had the boost set to 13psi, it was boosting fine, every now and then I would get a little hesitation from it, thinking that I am lacking on the fuel end of things, although still not hitting fuel cut. One day it just didnt wanna boost up to 13psi anymore, it seems to stay around 8-10psi now when I hit full boost. I swear its like the car has a mind of its own and gets an attitude with me at times. Well I have checked all of the intake piping for leaks and found nothing. I have even taken the vaccum line off of my manual boost controller and ran it like that, in this case it should run up to about 15psi and hit fuel cut, which it didnt, it stayed around 8-10psi, but it did pull pretty hard. I kinda think that I might be having problems with the gauge having a leak in the line or something and only getting about 10 psi to it. I really couldn't tell from the run I did without the line on. I think that it should have hit fuel cut with the line off, if it boosted up to 15psi, and it didnt. Has anyone had problems with the turbo only holding a lower boost than normal? Maybe going out or something? Or are there any other suggestions? Thanks a lot! __________________ 86.5 JSPEC 7MGTE 5SP, 14psi, HKS 2MM MHD, CENTERFORCE ST 2, 3" TURBO BACK, MANUAL BOOST CONTROLLER, JDM INTERCOOLER AND 2.5" HARDPIPES, APEXI NEO, WALBRO 255LPH, LEX AFM, DRILLED AND SLOTTED ROTORS AND RACE PADS, 18" STAGGERED 275/40 REAR, 245/40 FRONT. NEXT ON LIST: PAINT, JZA70 FRONT BUMPER, CARBON HOOD, RS RACE SPRINGS, POLY BUSHING KIT, SWAY-BARS.

06-04-2007, 02:19 PM	#2
ddmcse 500whp yet? Join Date: Jun 2005 Location: CT U.S.A. Posts: 966	it's always been a loose hose for me __________________ 300+ RW HP Dyno run, jdm,mod turbo,3"exh,electfan,greddyboost Blown HeadGasket info My Supra KiXGaS

06-05-2007, 03:35 AM	#3
supradad86_5 Stock Join Date: Apr 2007 Location: Bonney Lake, Wa Posts: 20	So this morning it boosted up to 13psi when the engine was still kinda cool, then after running for about 15 min it would only boost to 8psi. I rechecked all of the vac. hoses and intake piping, everything is tight and in it its place. I did run it again this evening without the wastgate acuator hooked up and it still boosted up to 8psi, so I am getting to the point that I think I can rule out the aftermarket gauge because if it did boost all the way up it would have hit fuel cut which it didnt. Any other ideas, anything would be helpful at this point. __________________ 86.5 JSPEC 7MGTE 5SP, 14psi, HKS 2MM MHD, CENTERFORCE ST 2, 3" TURBO BACK, MANUAL BOOST CONTROLLER, JDM INTERCOOLER AND 2.5" HARDPIPES, APEXI NEO, WALBRO 255LPH, LEX AFM, DRILLED AND SLOTTED ROTORS AND RACE PADS, 18" STAGGERED 275/40 REAR, 245/40 FRONT. NEXT ON LIST: PAINT, JZA70 FRONT BUMPER, CARBON HOOD, RS RACE SPRINGS, POLY BUSHING KIT, SWAY-BARS.

02-09-2014, 02:05 AM	#5
supradad86_5 Stock Join Date: Apr 2007 Location: Bonney Lake, Wa Posts: 20	This was a hose issue back in 2007, back when I still had a Supra. Thanks for the input though. __________________ 86.5 JSPEC 7MGTE 5SP, 14psi, HKS 2MM MHD, CENTERFORCE ST 2, 3" TURBO BACK, MANUAL BOOST CONTROLLER, JDM INTERCOOLER AND 2.5" HARDPIPES, APEXI NEO, WALBRO 255LPH, LEX AFM, DRILLED AND SLOTTED ROTORS AND RACE PADS, 18" STAGGERED 275/40 REAR, 245/40 FRONT. NEXT ON LIST: PAINT, JZA70 FRONT BUMPER, CARBON HOOD, RS RACE SPRINGS, POLY BUSHING KIT, SWAY-BARS.

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