Volvo Repair: 850 Turbo SportsWagon 1994, fuel pressure regulator, entrance ramp

Question
Mr. Patricio,

I'm an individual that loves driving a fine automobile and tinkering on cars. This is my third Volvo and the body needs much TLC but runs great thanks to the local shop servicing it through the years.

The problem is the 94 does not accelerate as you would expect with a turbo and cranks excessively to start, especially when the ambient temperature is 90F or above. A friend owns a V70 and to my surprise there is no comparison. Could there be that much difference in the performance of these vehicles?

I suspect the turbo is at fault because during the test drive I believe I heard the turbo when I started the car and felt it engage on the entrance ramp but not since. The engine did hesitated for a moment on the ramp as I cracked the throttle open (40-50 mph) and then without downshifting there was a huge surge of power which I took as the turbo engaging, maybe not.
I understand the principal of a turbo but not experienced working on them and would certainly appreciate your expertise on the subject.

Thanks,
Dean

By the way, the service light was on when I bought it. More importantly I found out after the fact that the gas tank spills gas (where the lines disappear over the top right rear corner of the tank) when it's topped off and wondering if this is related. At least a half gallon of fuel was lost before the leaking slowed just sitting there! The previous owner said he only noticed gas fumes coming from the back of the car and would only partially fill the tank to avoid the problem. The fuel is not leaking now and this will be repaired immediately but now I have a tank of fuel to consume before I drop the tank. I apologize for the long message.  

Answer
Dean, 850 Turbo chargers very rarely fail.  You may have a hole in one of the rubber hoses.  I would check there first.  Hard crank can be fuel pressure regulator or possibly an ECT sensor.  The fuel leak is a fairly easy repair but the tank needs to be dropped to replace the hoses on top of the tank. The Fuel pump assembly may also have a leak.  I have seen that before.  Hope this helped.  Roger