8psi?

[niddydsm]

So i have a 95 tsi and cannot figure the issue out. Driving hwy and boost hits 20psi (normal) oost control set, second run she only goes to 8psi and now it only hits 8psi. Ive check comp and its at 125 125 145 145. Ive pulled wg and still 8psi tried bov and still 8psi. Ive boost leak tested and fixed all issues. Ive run out of checks. N ed help as i dont know where else to look...

 

[3kgt2nv]

check all the couplers and pipes. ive had a coupler split from a rock kicking up and only cause a low boost issue since it would still partially seal and it looked fine when sitting. soap and water and looking for bubbles is what ended up finding it

 

[niddydsm]

Ill take the ic apart and inspect it again, but any other ideas? Turbo has minimal shaft play, no in and out.

 

[3kgt2nv]

i would start with a full boost leak test and was that compression test done hot or cold. 125 is low 121 is the service limit so you may be having internal issues also

 

[niddydsm]

I let cool down before I did the check.

 

[3kgt2nv]

the hotter the engine the better so the rings seal the best they can. go for a good 15 minute drive then do the test. idleing the engine takes to long to heat the rings since your not expanding the rings with boost/vac

 

[andrewshowers]

Sounds like a boost controller issue. Your WG pressure is probably 8 psi. What BC are you using? Is a line maybe broke somewhere?

 

[born2tune]

the hotter the engine the better so the rings seal the best they can. go for a good 15 minute drive then do the test. idleing the engine takes to long to heat the rings since your not expanding the rings with boost/vac

Yes, to an extent. the manual states the compression check should be done at idle temperature (doesn't matter how you get there, I prefer driving around the neighborhood at low RPM's until thermostat opens). so the hotter is not the "better".

the service limits are based off idle temperature. if done too cold or too hot, your numbers will be off.

Anyways, Im sure a compression check is not necessary in this case.

the boost controller in the other hand might be bad, leaking or even install backwards. or simply set way too low maybe like at 8 psi...

 

[niddydsm]

I have a hallman in cab boost control. I'm gonna completely pull the wg vacation line and try to run it. Ive done it before and nothing changed but I also had major boost leaks. Ill try it tomorrow and post

 

[niddydsm]

So i pulled the waste gate and only 8psi was hit. I pulled my down pipe and she pulled 17psi and held so i gonna say my cat is clogging up on this one.

 

[bryanwheat]

So i pulled the waste gate and only 8psi was hit. I pulled my down pipe and she pulled 17psi and held so i gonna say my cat is clogging up on this one.

What do you mean you pulled the wastegate. Did you remove the actuator or just remove the hose from the actuator?

 

[niddydsm]

Removed the vac source from the actuator.


I put a test pip inplace of the cat and 20psi was reached, so the cat was clogging up, atleast enough to slow my Turbo down.

 

[niddydsm]

Ok so after the test pipe was put on it hit 20psi for about an hour, now its back to 8psi. Could my egr be stuck open?

 

[crand]

how does the car drive other than the low boost? crazy the test pipe was only a short term fix, when do you start getting the low boost? when it reaches temp or randomly?

 

[Spoolin92GSX]

It sounds to me like the boost controller might be sticking. Hallman should be ball and spring type, just pull it apart give it a good cleaning and see if that helps.

 

[bryanwheat]

Check to make sure that the wastegate flapper is closing all the way, check to make sure that there are no cracks in the turbine housing, no pre turbo exhaust leaks, and no boost leaks. Also check the flex section in the exhaust to make sure it hasn't collapsed.

 

[niddydsm]

Checked flapper its good. I don't have any exhaust leaks. Car drives smooth doesn't bog at all no smoke. Ill take the controlled apart and clean it. I'm gonna do another boost leak test as well. Will post will results after thanks guys. It always has low boost it happened outage the blue and never went back up

 

[mattasi]

Have you done a boost leak test yet?

 

[GSTurbo1]

Have you done a boost leak test yet?

He stated he did, I would check all of your vacuum lines from turbo-bov-to wasted gate actuator. You may have a crack in your t fitting or small nick in your line. Check those over very thoroughly.

 

[mattasi]

Oh man, my bad I totally missed that , not sure how but I did.

 

[niddydsm]

Ive replaced the vac lines thinking they were old and cracking, that was my first assumption. I'm gonna try to make a block off plate for the egr tomorrow. I cleaned the hallman (wasn't dirty) no change. Again when i pulled the down pip she boosted fine. I've checked the entire exhaust system with a fine comb. Definitely running outa ideas.

 

[bryanwheat]

Ive replaced the vac lines thinking they were old and cracking, that was my first assumption. I'm gonna try to make a block off plate for the egr tomorrow. I cleaned the hallman (wasn't dirty) no change. Again when i pulled the down pip she boosted fine. I've checked the entire exhaust system with a fine comb. Definitely running outa ideas.

Why are you messing with all this other stuff if it boost's fine with the downpipe removed. It is pretty clear that you have a collapsed flex section on the downpipe.

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

 

[Firegst]

Why are you messing with all this other stuff if it boost's fine with the downpipe removed. It is pretty clear that you have a collapsed flex section on the downpipe.

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

X2 Good call sounds like he hit it right on the head.

 

[GSTurbo1]

Dude looks like somebodies arteries after 15 years of big macs and fries, don't forget the apple pie.... mmmmmmmm.

 

[92AWDHX40]

Wow thats crazy.