not hitting full boost

[S14tat]

what would cause the car to not hit full boost? lately my car have been hitting less and less boost. i'm only running 4 psi in first, 6 psi in 2nd and 7 psi in third.

if there was a boost leak, would the turbo be loud as hell tryin to make up for lost boost? becasue i don't hear a loud turbo at all. also i tightened every clamp and nothing i lose.

would a clogging cat prevent the turbo from making full boost? also i'm currently running orion's ECU while my original ECU is being reflashed at JWT. i felt the car miss fire once when i was in third gear. would a miss cause the car to not hit full boost? also would a clogged fuel filter make me not hit full boost as well?

and if its not that, then how would i check for a boost leak?

thanks alot guys.

[C-Kwik]

Several things can cause this. The first thing I usually suspect is a leak between the motor and the turbine. But you will usually hear this. A leak between the compressor and the motor usually is not heard, but tends to result in a very rich mixture and perhaps the motor will stall when dropping to idle coming off boost. A leaking or poor wastegate return line can cause problems with boost. A faulty BOV can exhibit signs of a intake side boost leak withouth the richness problems if it recirculated.

[S14tat]

well i just replaced my wastegate gasket, so the turbo i no longer loud. my car is only running slightly richer because im running orion's ecu instead of my mine. but i thought a leaky wastegate line would cause a over boost problem? and also my BOV is recirculated.

when i checked for codes, it says o2 sensor malfuction bank 1 # 2. so chances are i would assume its my cat going. however when i feel the exhuast pulses it feels fine. hmmmm

[Nismo_Freak]

I'd replace the cat with a test pipe and see what happens.

It does sound like a restriction mainly because as the load increases on the motor (related to speed) it is making more boost pressure. Basically the turbocharger is not getting enough energy to provide the boost pressure by either an exhaust leak, or by a clogged exhaust or intake.

I'd also take a good look at the wastegate to make sure it is not sticking open slightly. That would also have the same effect.

I'd get rid of the ****gate for a Tial 38mm too

[S14tat]

hahah well i would but i don't know about the clearance issue it will have with a Tial on a Revhard manifold.

also i unhooked the boost signal going to the waste gate, and i could not hit full boost till 4th gear. so its not the wastegate stickin either. yeah i suspect its probrably the cat. from those symptoms it doesn't sound like a leak in the intake section no? i guess if it was leak in the intake, it wouldn't build more boost in different gear and rev? thanks for the help guys.

[Structure240sx]

the tial is a direct replacement for the deltagate on the revhard and maybe any application. i personally have a revhard mani have have had both wastegates.

could still be a boost leak. i had my old bov pop off the IC piping before. car could hardly make any boost. also didnt idle to well. check for any openings in your IC, IC piping, couplers, and bov

[S14tat]

well the car idles beautifully with a strong vac of 22 inhg. i've had this problem before, but it was a broken vac line at the wastegate. but i checked that and i even trimed off the slightly hard end that is hooked up to the wastegate and still no luck.

how small does the hole have to be for it to leak that much boost though?

also my pedal feels alittle stiffer.
Modified by S14tat at 10:25 PM 11/19/2004