No boost problem

**Slowbaroo** · 06-21-2010 04:42 PM

I have a 2002 wrx with a VF-39 and a GM BCS, and stock BOV, it was running great and then all of a sudden yesterday i went to get on it and there was no boost. My car still runs fine idles fine accelerates fine, its like nothing is wrong its not even smoking but you can smell that it is running rich. vacuum is reading 20 psi and idle but when i accelerate and should be hitting boost the gauge just sits at 0 pounds still not smoking or running any different then idle but there is absolutely no boost. Does anybody know what could be wrong, and how to test it????

**Anub1s** · 06-22-2010 12:50 AM

Take a look at the wastegate actuator, the valve could be stuck closed.

**Sinister** · 06-22-2010 01:27 AM

if the wastegate was stuck closed... then he'd be overboosting. It may be open. Wastegate pressure is 7psi, so if a vac line was busted, or the BCS wasn't working... then you'd be boosting to 7psi... But depending on where you're reading your boost pressure from... That may be the case.

**Slowbaroo** · 06-22-2010 04:23 AM

I am reading boost pressure from the BOV

**Sinister** · 06-22-2010 05:23 AM

Do you have an aftermarket up pipe?

This sounds suspiciously like a turbo that got hit with shrapnel and seized up.

The only things this could reasonably be are:
The wastegate arm is stuck in the open position.
The oil coked and your bearings in the turbo siezed.
the turbo FODded out (FOD Foreign Object Debris... a.k.a. the pre-turbo catalytic converter, also called the precat, had a chunk let loose and jam the turbine wheel)

**Anub1s** · 06-22-2010 06:20 AM

Thanks for the correction Sinister, apologies for the typo.

**Sinister** · 06-22-2010 06:25 AM

Originally Posted by Anub1s

Thanks for the correction Sinister, apologies for the typo.

**Slowbaroo** · 06-23-2010 04:37 AM

should i be able to move the waste gate actuator all the way back with my hand with only using a little bit of force?

**Sinister** · 06-23-2010 05:05 AM

Originally Posted by Slowbaroo

should i be able to move the waste gate actuator all the way back with my hand with only using a little bit of force?

There is a 7lb spring in there... so it'll take a bit of a push.

Do you have an upgraded up pipe?

**Slowbaroo** · 06-23-2010 08:30 AM

ya i do but i dont know what kind it is i bought the car with it on

**Sinister** · 06-23-2010 09:55 AM

Originally Posted by Slowbaroo

ya i do but i dont know what kind it is i bought the car with it on

does the up pipe have a catalytic converter?

**NRD** · 06-23-2010 11:13 AM

i agree with sinister...but here is another way to check (if you have time and you are mechanically inclined)
grab yourself a:
1. 3/8 ratchet. 10mm, 12mm, 14mm, 17mm sockets.
2. 1/4 inch ratchet. 8mm, 10mm sockets
3. 3-6 inch extension for a 3/8 ratchet
4. alot of rags
5. some oil (5w30)
6. coolant
7. flat head screwdriver

first, remove your intercooler completely. take the heat sheild off of the turbo. remove the oil supply line on the top of the turbo. remove the coolant supply line from the side of the turbo. depending on what make/model your car is, it might have a coolant return line on the opposite side of the turbo too, if it does, remove that as well. after you have removed all of that, remove your down pipe. remove your turbo inlet hose. now that you have everything disconnected from your turbo, its time to remove it. there are 3 14mm nuts that hold it in place. remove those. after that you should be able to pull it off of the up pipe. keep in mind, there is an oil return line on the bottom of your turbo. make sure when you install the turbo, you slip it back to where it belongs or you will have oil spilling everywhere.

once you get the turbo off, check it theroughly, check for shaft play, schrap metal, wastegate abnormalities, or anything out of the ordinary.

make sure you check all of your intercooler couplers and seals too, because if your turbo is fine, you might have a boost leak.

hope you found my answer helpful

Originally Posted by Sinister

Do you have an aftermarket up pipe?

This sounds suspiciously like a turbo that got hit with shrapnel and seized up.

The only things this could reasonably be are:
The wastegate arm is stuck in the open position.
The oil coked and your bearings in the turbo siezed.
the turbo FODded out (FOD Foreign Object Debris... a.k.a. the pre-turbo catalytic converter, also called the precat, had a chunk let loose and jam the turbine wheel)