I bought a 1989 Volvo 760 Turbo about a year ago. It sat because it needed a timing belt. We finally got the timing belt changed and it wouldn't start. No fuel coming through the lines. So we changed the fuel pump, it still wouldn't work, THEN we also changed the fuel pump relay and it was now getting fuel but wouldn't start still. Then we cleaned the injectors and fuel rail. Now it started up.

I took it for a drive and it was running fine. I put some seafoam through the vacuum lines and some in the tank and put fresh 87 octane gas in it. When I was driving home I noticed it started to bog and when I tried giving it more gas it stalled out on me. Now It keeps doing that. As soon as the turbo gauge goes more than half up into the solid white line it starts bogging down. As long as you feather the accelerator and keep the turbo boost gauge below 50% it will not bog at all.

Any suggestions will be appreciated. I don't know too much about these cars and I'm tired of just throwing parts at it. I was thinking about also changing the fuel pressure regulator. The fuel pump was definitely bad though because the one we pulled wouldn't run even with direct 12v from battery and the new one we got would run with direct 12v from battery. The fuel filter is also new. As is the distributer.


The car is FINE when it's cold. If you let it sit and it cools down it will run perfectly fine. HOWEVER as soon as it warms and you give it gas as long as the turbo needle hits half way point it starts to stall the engine.

 

So, it runs fine while cold, bogs down once warmed up? So, something expands or gets hot... It may be the turbo, it may be the fuel pump, NOT the FPR, leave that... OR you may just have a HIGH SPEED MISFIRE affecting performance. I'd go with the latter first. May be a wire/plug/coil problem, i.e. a "tune up" thing...