Too much boost

[Bernie Steffen]

Am new to the world of GN. So I have some problems I need help working out. First I bought my 85 in pieces. the engine block was bare. I Had the block bored out and put it back together box stock. Two main problems I can't get the boost down low enough. It'll peg the gauge if you let it. thats aftermarket gage. Next it won't idle after it warms up. I've been a mechanic most of my adult life I'm 69 years old No I'm not too old to be messing around with these thing. I like to play. anybody got any suggestions? I was thinking maybe I had a problem with the egr valve. thanks in advance for any information you can give me . Bernie Steffen zstef@mchsi.com

 

[SLOW_85]

I'd start by checking your vacuum routing for the turbo.
Also need to make sure you have the Y with the orifice in the line from the turbo to wastegate actuator.
Could be a vacuum leak or bad IAC on the idle.
Check out the sticky at the top of the forum.
http://www.turbobuick.com/forums/showthread.php?s=&threadid=33080
HTH

 

[Bernie Steffen]

too much boost No hot Idle.

Bob Thanks for the comeback and the info. Now to show you how misinformed I am what is a IAC. I installed all new vacum lines per the diagrahm on the fan shroud. I noticed when I bought the car the ring lands on the second ring were all pushed down. Broken. I supposed this could be caused by too much boost.. The car had had a aftermarket vacum gage installed in it because there was a vacum line in the drivers compartment that wasn't hooked up to anything. Someone had also cut the rod on the waste gate actuator and installed a coupling. I was talking to Tony at Postons and got the correct measurements for the rod and set it to the correct length. I checked the diaphram onthe actuator with low air pressure and it seems to be OK. LIke I said I've been a mechanic for most of my working career but overthe road trucks and railroad mechanics don't tell you much about a GN. I also have a S-10 pickup with a 455 Buick engine. Any thing you can help me with will be greatly appreciated Oh the Y is in the vacum line to the wastegate I have the double line wastgate Thanks again Bernie Zstef@mchsi.com

 

[SLOW_85]

I didn't think about the wastegate being adjustable.
Tried to cover the basics first.
On the idle hard to check much without a scan tool.
The IAC can be cleaned,it's under the throttle body.
Just be careful tightening,the housing is aluminum and will break.
Also any vacuum leaks will cause a rough idle.
Folks will help you out here,just ask!

 

[BRAD_PADGETT]

I have an 85GN with slight mods and can help you with pics of how all the vacuum lines run. Send me an e-mail- Brad