Car only gets 15psi

[Buickforlife]

I am having some issues with my car. The boost will only go up to about 15psi, and I had it running 22psi. It started doing this after my MAF inlet pipe for some reason came loose at one of the joints and it started running terribly. I limped it home, (only going about 30mph) and popped the hood, and fixed that problem, and it immediately ran perfect. But I drove the car today, and it will only build up 15psi. I have checked for vacuum leaks, and pulled off the intercooler to make sure that the little fan has not rubbed a hole in it. Can't find any reason why it would have changed.

I did pull off the downpipe, and the elbow to check on the wheel, and it looks fine, could this be an issue with the wastegate? I tried adjusting it, and the boost pressure stayed the same. I don't know what to do! Any help/suggestions are much appreciated!

 

[Buix893]

Could be the wastegate hole not lining up, mine was off a little bit and could only muster out 14 psi, then got it fixed and back to 23. Do you have a Cat on the car?

 

[Buickforlife]

Could be the wastegate hole not lining up, mine was off a little bit and could only muster out 14 psi, then got it fixed and back to 23. Do you have a Cat on the car?

Yep, I have the stock cat. Can the wastegate puck not line up right just suddenly like it did?

 

[Buickforlife]

The wastegate puck is definatly lining up. I am wondering if this could be a wastegate actuator problem? I tried adjusting it earlier, and the boost stays the same.

 

[1quick6]

Did you check the vacuum lines going to the wastegate actuator? You didn't disconnect them while fixing the MAF pipe or checking other stuff, did you?

 

[Buickforlife]

Did you check the vacuum lines going to the wastegate actuator? You didn't disconnect them while fixing the MAF pipe or checking other stuff, did you?

I've checked them 3 or 4 times now. I might check them again just to be damn sure they are on.

 

[turboc87gn]

Check the bottoms if all your intercooler and up pipe joints mine had a hole blown in it right after i blew a pipe off it looked like a small tear and was barely noticeable!!!!

 

[1quick6]

I've checked them 3 or 4 times now. I might check them again just to be damn sure they are on.

I'm just asking because if they are backwards you will experience limited boost. I wasn't sure if you had removed them when fixing things. Yes, like the above poster mentioned ... that has happened to me. The hose connecting the up-pipe to the intake had blown off underneath and I didn't notice because it wasn't visible and passed the initial finger test.

 

[Buickforlife]

Check the bottoms if all your intercooler and up pipe joints mine had a hole blown in it right after i blew a pipe off it looked like a small tear and was barely noticeable!!!!

I just got new silicone hoses, I will go and check them just to be sure.

 

[Buickforlife]

I'm just asking because if they are backwards you will experience limited boost. I wasn't sure if you had removed them when fixing things. Yes, like the above poster mentioned ... that has happened to me. The hose connecting the up-pipe to the intake had blown off underneath and I didn't notice because it wasn't visible and passed the initial finger test.

I didn't have to mess with the wastegate vacuum lines, but how can you get them backwards anyway?

 

[Buickforlife]

Any other ideas?

 

[Junior Samples]

you got serious side play on your impeller wheel and its headed for destruction, It happend when you hit that giant sinkhole at the corner of Saginaw and Atherton

 

[Buickforlife]

you got serious side play on your impeller wheel and its headed for destruction, It happend when you hit that giant sinkhole at the corner of Saginaw and Atherton

I did notice that the impeller wheel had some side play in it. I guess it's time for a rebuild.

 

[Junior Samples]

I did notice that the impeller wheel had some side play in it. I guess it's time for a rebuild.

And there you have it

 

[Buickforlife]

And there you have it

I went and checked, it has some movement, but I wouldn't consider it some serious movement.

 

[Buickforlife]

Pulled off the cat, and it wasn't clogged. The exhaust was clogged with a chunk of the interior of the cat!

After I got that out I gutted the cat just cause, and put it back on, and I now have 22psi.

Thanks for all the help and suggestions everybody!

 

[Buickforlife]

Well, now that the boost issue is fixed, I have developed another issue. The car stumbles when I try to brake boost it, and when I am accelerating it seems like it is missing. I think that it is an ignition issue. Maybe the coilpack?

 

[robertmee]

and/or the ignition module....

 

[Buickforlife]

and/or the ignition module....

I sure hope it isn't the ignition module.