Boost is there but not workin

[cruisintalonawd]

I punch the gas and the gauge reads 0 untill about 4000RPM then it starts to build boost but none of it is applied. I have done boost leaks before and after this problem and they have not changed. Could my MAF be bad or something worse?

 

[PIMking]

are you reading the stock gauge? or do you have an aftermarket gauge?

 

[hdoerr]

well I bet your waste gate is stuck. Also the stock gauge is a mathematical calc. not an actual reading.

 

[cruisintalonawd]

after market gauge and I have tried to even unplug the wastegate

 

[hdoerr]

Well if it is stuck open it wouldn't matter if you unplugged it.

 

[cruisintalonawd]

you're right. it is stuck open a little bit.

 

[cruisintalonawd]

what would I do about the boost being there but not applied

 

[tbonitz301]

Get your wastegate to seal

 

[cruisintalonawd]

Its not that I just rigged it so it stayed shut and it still did the same thing

 

[tbonitz301]

Start looking over your turbo. Do another BLT. There's gotta be somethin leaking. Check your compressor housing, and all that good stuff

 

[cruisintalonawd]

yes there is leaks but they werent effecting the car for the last month

 

[cruisintalonawd]

so anyone have an answer

 

[knochgoon24]

Fix the leaks

 

[TSI95FWD]

bump

 

[cruisintalonawd]

So your saying after a months time the leaks are finally catching up with everything else? That makes no sense. I was doing another BLT and put it to 20 psi and about 30seconds later the tester blew clean off the compressor housing inlet. The only 2 places its leaking is the throttle body shaft and the compressor housing where that snap ring goes

 

[knochgoon24]

I know I have a boost leak and as soon as it stops raining here, I'll fix it. But I'm having the same sort of problem. I hit the gas, but the boost doesn't throw me back in the seat like it used to. I used a logger and noticed that I'm reading wayyyy more air with the MAF than I used to, that was my give away.

Are you using any type of logger?

 

[kenamond]

So your saying after a months time the leaks are finally catching up with everything else? That makes no sense. I was doing another BLT and put it to 20 psi and about 30seconds later the tester blew clean off the compressor housing inlet. The only 2 places its leaking is the throttle body shaft and the compressor housing where that snap ring goes

Find out why your WG wasn't staying closed and fix it.

Check your turbo for excessive shaft play.

When you applied 20psi, you stopped applying pressure and it held for 30 seconds and then popped? Or did you hold 20psi from a compressor with the regulator set to 20psi and it popped after 30 seconds? You need to apply 20psi and then stop. Then you see how fast the boost gauge pressure drops from 20psi. My car drops 1psi every 4-5 seconds from 20psi initial pressure. If you leak down too fast, fix the leaks. VFAQ has the how-to for fixing TB shaft seals. If your compressor o-ring is leaking badly, I don't know if you have to fully rebuild it or just replace the o-ring (ask someone or search).

Do you have a logger? If so, anything look weird (knock, low O2v, etc)? If not, they're cheap for you lucky 1g owners.

 

[vancitydsm]

You could have a plugged cat, take off your downpipe and drive around the block see if it changes. If not put back together. It seems like a turbo leak problem but if you have minimal leakage you won't notice it much and thats true. You MAFS could be a problem.Check your airfilter, stuff like that.

 

[cruisintalonawd]

I have the palm M100 that it is actually reading only about 1100 whatever at 5000 rpm. The turbo has minimal shaft play and spins freely. I don't have a cat and I've tried driving around without the air filter and that didn't help. I'm not try not trying to me ignorant or anything but I don't think its the boost leaks because they have been the for a while with the car running good

 

[kenamond]

I have the palm M100 that it is actually reading only about 1100 whatever at 5000 rpm. The turbo has minimal shaft play and spins freely. I don't have a cat and I've tried driving around without the air filter and that didn't help. I'm not try not trying to me ignorant or anything but I don't think its the boost leaks because they have been the for a while with the car running good

1100 whatever? Please explain what value that is. A log would be nice.

Please explain what you did for your BLT. I'm not trying to offend you, but folks often misunderstand the test procedure and I just wanna make sure you're doing it right. Also, new boost leaks can develop, so if you haven't tested (correctly) since the problems started, I'd re-test.

Did you figure out why the WG wasn't staying closed?

Are there any diagnostic trouble codes stored?

 

[rarson]

By 1100 I'm guessing he means Hz.

 

[booostedGSX]

Possibly a terrible exhaust leak before the turbo? I had a blown turbo gasket and it seemed to not want to build boost at all.

 

[cruisintalonawd]

the WGA arm is extened to far I got a new one. HZ is what it is was I believe. I've tried to put a log onto the computer but it didn't work. The way I do a BLT is I have a peice of PVC piping that has a air connection on the end of it that hooks to a air hose and it then I use the regulator to control the psi, then spray soapy water everywhere.

 

[cruisintalonawd]

Ok so I did a compression test and I had 125 on all four cylinders. (On a brand new 8:1 motor) Then I looked at the cams and the intake cam was about 4 or 5 teeth off so I tried moving the cam the ghetto way and went the wrong way. Then I finally got them back on track and now the compeasion is 100 on all four cylinders.

 

[rarson]

What?