I have a 1994 850 turbo 156,000miles, automatic. So after a sudden drastic drop in mileage) from 30 to 17 mpg.... I just spent a ton of time and $$ replacing plugs, dis cap, wires, fuel filter, O2 sensor and cat convert. All of which should have been done a while ago when I bought the car. LESSON LEARNED. While addressing that issue I was told I have no boost in my turbo. While the car is no longer seriously hiccupping and stuttering above 60mph (I have only driven about 15 miles since the final repair) and I have little to no power. I have had the car for 3 years and the boost gauge on the dash has never gone into the white even when flooring it. I dont drive this thing hard though, so I never made anything of it. I take of slowly and dont push it, but is drags. Now it seems that drag is worse than ever and getting up to 65mph is like pulling a trailor. This might not even have anything to do with the turbo? but The turbo doesnt engage at all.

I have no smoke, engine is staying cool.

I found a ripped hose connecting the BCS and the CBV so I replaced the those small hoses from the BCS which were nice and crispy. This made no difference. Checked the wastegate...works...checked the shaft... good not much play.

People have been mentioning to check the intercooler hoses and I have but still found no leaks. They are however getting soft. Also I am getting a very steady womp-womping sound I get when i accelerate and when I am driving with cruise control on the hwy.

I have revved the engine and squeezed the intercooler piping for pressure and it seems to hold pressure yet the wastegate is not opening (however the wastegate works). I have done a pressure test into the CBV and the rod moves to open the wastegate so somewhere I am loosing pressure...right? Could I have a bad boost control solenoid? Is there some sort of back pressure problem? I am going to investigate the intercooler hoses more still. I have read a few threads that seem to have a similar problem but never a final solution. Anything else I can do besides rebuild the turbo? My pockets are not that deep right now.

If I drive the car long distances as is am I going to destroy the engine? Thanks for your help!

 

Sounds like you need to pressure test your turbo path. To me, you have a leak in your intake that is not allowing boost to build.

You never know where they will pop up, hoses dry and burst and can appear fine. Pressure test it.

 

Will the PCV system effect the turbo boost? Have you had the PCV system replaced in the past 60,000 miles? Does the boost gauge more at all (down or up)?
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