5psi no more no less

[90gs-turbo]

While driving the car I can only get 5psi max needle hit 5 and stays there as if I set my boost to five .It wont stop on 4 wont go to 6 as if I had a leak and well I cant find a leak..I have a aftermarket boost guage ...Any takers

 

[tom1995tsi]

Uhhh your wastegate actuator has a 5 psi spring??

 

[90gs-turbo]

UMMMMM could you explain that a little more...A 5psi spring

 

[oldman]

UMMMMM could you explain that a little more...A 5psi spring

Which turbo do you have, fill out your profile completely. 14b or 16g turbo comes with 14psi wastgate actuators which means the min boost you can run is 14psi. Sounds like your wastgate is stuck open if you're only getting 5psi. Make sure the actuator arm didn't fall off.

 

[SlowSpyder]

14b/16g come with a 7-9 psi actuator not 14. Unless your running an external wastegate with a 5 psi spring, Id say you have a leak in either the intake or the exhaust.

 

[oldman]

14b/16g come with a 7-9 psi actuator not 14. Unless your running an external wastegate with a 5 psi spring, Id say you have a leak in either the intake or the exhaust.

I thought it's 14 because when I bypass the mbc and run the boost source directly to the actuator, I get 14psi.

 

[90gs-turbo]

Ive got a 14b turbo..How do I tell if my acuator is sticking open...I have checked the intake and exhaust..No leaks

 

[oldman]

Ive got a 14b turbo..How do I tell if my acuator is sticking open...I have checked the intake and exhaust..No leaks

1. Make sure the arm is connected to the wastgate door lever right smack in the middle openning at the bottom heat shield.

2. The positin of the lever should be pointing down (closed), not to the driver side (open).

3. Try moving the arm, it shouldn't move.

4. Find a DSM friend who has a 14b or 16g and swap the actuator.

 

[91Bomb]

My '91 tsi has a wastegate solenoid valve that limits boost to 7 lbs -- no more no less -- when knock is detected OR if the solenoid valve itself gets either stuck open or closed (not sure which).
It's a failsafe designed to limit boost to a pre-set amount when knock (or phantom knock) is detected as to help protect the engine from damage.