BOOST GAUGE PROBLEM!! Please Help!!

[joelude]

I sure hope this hasn't been posted before as I have talked to so many shops and people with some knowledge that they are all stumped also. Over this past weekend I installed a Greddy 60mm black faced boost gauge into my '90 Turbo Laser RS. The gauge, from what I am told, is working the exact way it should be working except for one problem... when I mash on the gas and shift at full boost the Greddy gauge is at about 1.5 - 1.8 bar! Thats just not possible on a stock turbo! I dont know what is causing this. Anyone ever had this problem or know how to fix it? I "T"d the sensor hose into the vacuum line that runs from the intake manifold up to the fuel pressure solenoid. Is that causing the problem? Please help me!

 

[PaleDSM]

Boost that high is possible if there is a problem and the wastegate isn't opening at all.


Double and triple check your pressure signal line. Make sure it is something right off of the intake manifold. If that checks out double check your wastegate and actuator.

 

[joelude]

If that checks out double check your wastegate and actuator.[/QUOTE]

How exactly do I do that. I remember reading on here or somewhere that you use a hose attached to a bicycle pump and attach to the wastegate actuator. Is this true? And what exactly am I looking for it to do? Can you point me towards the post that has this info?

 

[PaleDSM]

Supply pressure to the wg actuator. 12+ atleast and watch to make sure the actuator is opening the flapper door of the wastegate completely.

 

[joelude]

So I can look down in the engine compartment at the wastegate actuator while I am applying pressure to it and can watch the flapper open? Or do I need to remove some things in order to get a clear view?