My 87 Turbo Regal is making too much boost... Help

[1BUICKT]

Hello everyone. New member here with a bit of problem that Im needing some help with.
Since purchasing my Regal back in September I have done the following mods... replaced the stock turbo with another used factory unit (the nut on the impellar shaft came off the original which caused havoc inside the turbo), replaced the fuel pressure regulator with an adjustable Accufab, added a Racetronix Hot Wire kit, and also ditched the Pit Bull chip with a 91 octane friendly Turbo Tweak chip. I also added Pro-Comp fuel pressure & boost gauges. The problem Im having is the car will boost all the way up to 20+psi... I have the gauge on it so I do my best not to let it get over 17psi (seems totally fine at that psi) when accelerating. After going through some of the archives here I figured the boost control solenoid must be what was causing this problem so I replaced it with a new ACD# 214-1073 and a Casper harness to mate the factory plug. I took the car for a spin this afternoon and the boost is still wanting to climb as high as before. Any ideas on what is causing this? The wastegate actuator is the factory non-adjustable piece btw.
Thanks,
Johnny

 

[keith theriot]

i would think that it would be the actuator,

 

[Razor]

Any breaks or cracks in the WG hoses will create problems. As well as any issues with the WG itself. The WG is basically a rubber ballon inside the can. You can test it using a mity vac pump.. it should hold air.
If you plug the hose going to the solenoid that will be minimum boost. The solenoids bleeds air off to increase boost. If minimum boost is still too high.. you need a new WG diaphram.

 

[trbojo]

bad w/g actuator, pinhole leak/dry rotted hoses, wrong/missing/incorrectly oriented "y" orifice......

 

[1BUICKT]

If you plug the hose going to the solenoid that will be minimum boost. The solenoids bleeds air off to increase boost. If minimum boost is still too high.. you need a new WG diaphram.

I can try this and see what happens. When you say "minimum boost" what kind of number should I be looking for? Please bare with me if this seems like a dumb question... Im new to turbo buicks and learning as I go.

Btw, thanks you guys for the replies! I appreciate it.

 

[Razor]

13-14 PSI?

Make 100% sure the hoses are not rotten from turbo to WG. There is a Y fitting as well. Any breaks in that line will create your problem.

Boost is controller by air applied to WG diaphram. The more air(from compressor on turbo) hits the diaphram, the more the rod extends, the lower your boost will be. If you have any air breaches in those hoses.. the WG will not see 100% and boost will increase.

 

[1BUICKT]

13-14 PSI?

Make 100% sure the hoses are not rotten from turbo to WG. There is a Y fitting as well. Any breaks in that line will create your problem.

Boost is controller by air applied to WG diaphram. The more air(from compressor on turbo) hits the diaphram, the more the rod extends, the lower your boost will be. If you have any air breaches in those hoses.. the WG will not see 100% and boost will increase.

The hoses with the Y fitting were just reinstalled by myself at the time I swapped the turbo.. they all looked great with no cracks or flaws. The car has been sitting for about an hour or so and I will go out and double check again to be sure before plugging the line and running it.

 

[blackdeathtrap]

set it up tunner style se if you get min boost basicaly take vacume line from waiste gate actuator to cold side of you turbo basicaly bypassing you computer control over the boost it should be 13 14 psi if not heres your hint your actuator is fucked

 

[1BUICKT]

I double checked the hoses and fitting and everything looked A-OK so I went ahead and plugged the line and took her for a spin. The car spooled up just like normal and I backed off when it got to right around 17-18psi.

 

[groumoutis]

Have you checked the gauge to make sure it is not out of calibration? Hook up some shop air regulated down to 15psi and see what the gauge says.

 

[1BUICKT]

Have you checked the gauge to make sure it is not out of calibration? Hook up some shop air regulated down to 15psi and see what the gauge says.

I did consider it and I believe the gauge is definitely functioning properly.

 

[Razor]

I double checked the hoses and fitting and everything looked A-OK so I went ahead and plugged the line and took her for a spin. The car spooled up just like normal and I backed off when it got to right around 17-18psi.

Stuck puck arm in elbow? make sure it swings freely.. disconnect arm and make sure the puck moves freely.
Or bad WG diaphram.

If you unhook the WG arm from the turbo it will be at minimum boost. Assumming puck arm swings freely and is not shut/frozen/seized in place.