Can't build boost and new noise

[BrentNKC]

Hello,

I just purchased an 87 GN and added some modifications. Unfortunately, I did them all at once so it will be harder to troubleshoot and now can't build boost past 11psi according to factory boost gauge. Before changes the guage showed about 17psi. I added new TT chip, RJC Power Plate, 3" downpipe, R43TS plugs gapped at .035. I tried adjusting the wastegate tighter a few turns and then take a run test and by 10 turns in total it only added 1 psi of boost. After my last test run, I started hearing some noises in the engine. I am now afraid, I may have a more serious problem in the engine that is not allowing boost. I had a scanmaster hooked up and there was 0 KR and O@ was over 750. Any ideas?

Thanks!

 

[bluettype]

did you remove the wastegate vacum lines? check and make sure the restrictor in the y connector is on the compressor side going to solinoid, mine was wrong and all i could get was 11#.also get an aftermarket gauge

 

[BrentNKC]

Thanks for the reply bluettype. I did some further checking
and started the car today and it sounded okay. After a drive around the block the car smoked badly whenever it tried to boost. Otherwise ran fine, did not overheat and maintained oil pressure. I checked the tailpipe when home and it contained alot of oil around the inside. Is it possible for a turbo to do this or am I looking at a rebuild?

Thanks!

 

[SGRIM]

Sounds like the turbo is going or gone....

Welcome to TurboBuick.com btw!

 

[BrentNKC]

Thanks SGRIM,

I hope it is the Turbo. It should be much less expensive to replace than a headgasket or engine rebuild. Do you know how I can tell for sure?

Brent

 

[johnplogii]

Pull the air intake tube off of the turbo & check the turbo compressor wheel for play (up & down and in & out) play should be minimal. Also pull the intercooler pipe off of the throttle body & look for oil.

 

[BrentNKC]

Thanks John,

That will be my next step. Is there any way the engine can cause the Turbo to fail. I am just hoping that it is only the Turbo that is messed up.

Brent

 

[johnplogii]

If something goes through your exhaust it can ruin the turbo, yes. I had a small peice of metal header gasket take out my turbo last year. Also a lack of oil to the turbo will do damage, but it sounds like its getting oil.

 

[BrentNKC]

Thanks for the info!