98 gst chokes

[Luis De Leon]

I recently upgraded the intercooler on my gst but now when the car hits around 5000 rpms it seems to choke. The car seems like it wants to pull but just lags in power. When I first got it I had the same issue but I replaced the spark plugs. I got them from the dealer and it solved the issue.

 

[Dsmkauai]

Boost leak test!! Anytime you mess with the intake track you need to do one!

 

[Silver gryffon]

Agreed. Test for boost leak.

 

[Luis De Leon]

I was driving home and noticed the boost gauge goes up to 25 psi and that's when the car starts to act up .

 

[jerrylarsen]

stock boost gauge or after market?

 

[jerrylarsen]

if its stock, they read load more than psi. if its after market youre hitting fuel cut and need to figure out why your wastegate isnt opening.

 

[jerrylarsen]

make sure your actuator vacuum line is hooked up on both ends, if you have a boost controller verify its hooked up right and working properly

 

[Dsmkauai]

25psi! Woooh better not do that again bro. Your wastgate might be stuck. We really need to more about the car and setup.

 

[stiggity99]

if the problem starts acting up around 25psi, be sure you gap your plugs according. I had to gap mine to .025 just to run 24psi... on a big 20g..

 

[pmillerlite]

I would also say a boost leak might be the issue.

 

[Luis De Leon]

The car still has stock turbo all I have done to it is the front mount intercooler, injen intake and hks bov. The gauge is aftermarket and I don't have a boost controller yet and all lines are on good .

 

[Silver gryffon]

The stock turbo shouldn't be hitting 25psi.

 

[rough]

Your Stocker "T25" won't last long hitting 25psi
I'm still on the T25, and she will lose power up top when I boost over 14/15psi.

 

[Nick97dsm]

watch out running a turbo at to high of a boost level you run a chance of turning that turbo into a detonating bomb that will kill your motor and anything around it. take a super big amount of caution, watch the youtube videos of turbo explosions.

You must be logged in to view this image or video.

 

[rough]

That video is from 1985.. I was 3.. going old school!

 

[Teezy]

Assuming that your car is stock in its entirety besides adding a front mount to probably just look "cool". The stock turbo most likely will not provide sufficient pressure at lower RPMs because it isn't tuned, and the intercooler is too big for it. The stock T25 turbo maxes out at about 15 psi and after that you're just blowing hot air into the motor which isn't very good at all. Also, make sure your BOV isn't blowing off into the atmosphere because you're losing metered air and just dumping fuel into the combustion chamber. Recirculate the BOV back into the intake pipe so it won't run like shit. Don't drive the car until you fix any and ALL boost leaks and ditch the front mount since it's totally unnecessary.

 

[Nick97dsm]

its old school but the same concept.

 

[rough]

The front mount is ok on the T-25 as long as it around 24 x 12 x 2 or 2.5
I felt nice gain when I put my FMIC on. Spool stayed the same as I didn't opt for a 3" 30x 20 size which anything around this size will hurt airflow/volume on the tiny T25.

I never have a issues heat soaking, and she pulls harder, longer up top. Still falls on her face about 6000, but that's better then the low 5ks I was feeling before.
Plus I don't have to install the FMIC for the 16g, just tweak the lower inter cooler pipe!

 

[Luis De Leon]

Thanks everyone I'm taking the car to the shop soon get it checked out. I got a boost controller already and looking to get a 16g turbo and getting the car tuned too.