won't build boost

[87 national]

Having trouble after pulling the car out after the winter it will only build 4 psi.
checked all the basic
vac leaks
checked for leaks in the intake
checked for exhaust leaks
wastegate
boost control
downpipe pluck
I am at a lost any ideas?

 

[phil_jordan]

Is it popping? Does it take it a while to build the boost? I would potentially check the throttle and be sure that the blade is opening up all the way when flooring it.

 

[phil_jordan]

Just a thought tho

 

[Hatdragracer]

Fuel Pressure while running and under boost? Any scanmaster numbers?

 

[AN/GSC-52]

I put a cooper downpipe gasket in and it was keeping the WG open. Just a thought

 

[SS/GN]

Waste gate control??Try RJC just to compare??

Kevin

 

[87 national]

Runs fine no poping throttle is opening all the way. Will get scanmaster numbers. copper rtv on down pipe so no problem there. disconnected boost control and slowly layed into the throttle to see if it would build boost so no need to try different boost control. No idea what to check.

 

[KEVINS]

Does the turbo spin freely?

ks

 

[87 national]

it spins freely and no play

 

[Daniel Jost]

Have you tried disconnecting the boost ref. line to the Wastegate can? Also try and disconnect the actuator and see if you can pull the puck lever any further closed.

,Dan

 

[IowaGN]

I am having this exact issue right now as well. I've spent a good part of my day diagnosing this and no conclusion yet. Car drives just fine otherwise. Just won't build any boost whatsoever and like the OP, it ran great earlier this year and now, poops all over itself.

 

[Amelio]

Is this problem overall? It will not build boost from a roll or are you just having a problem building boost from a stop to launch the car?

 

[IowaGN]

In my case both. Seems like I try to get anywhere above 1/3 throttle and she just spits sputters and generally runs like crap until i let up a little bit then all is well. My friend came over this afternoon and we used his powerlogger to log idle and an attempted brake stand. The only thing we have not been able to check is fuel pressure when this is happening. I have a rail mounted gauge and doing the brake stand in the drive it rises as rpms do, and still zero boost. We did get one odd thing to happen during a test drive. Once I got above 55 mph and tried rolling into it, I saw 10 lbs on the boost gauge byt the car sure as hell wasn't acting like a car under boost. I can email anyone who wants to look at it the log.

 

[Boost_N]

Just a thought tho

I know this is old but did anyone ever figure out what the problem was.