Hello all-

My brother down in NC has an '87 745 M46 non-turbo. Only problem in the past year or so was bad fuel pump relay, bought new Volvo unit, car ran fine.

The other night his wife drove the car to class, ran fine, drove home, car wouldn't pass 2000 rpm in gear. Car hobbled home, will idle fine, rev up to higher rpms in neutral fine, just don't try to drive it anywhere.

I'm in CT and we've both been reading the FAQ.

I had him pull the AMM to intake hose, he's found a few smallish holes, I'm having him clean, duct tape, and test. I really don't think this is causing the problem, but won't rule it out. I doubt these holes appeared while his wife was in class.

He's disconnected the AMM and the car ran poorly with no change in performance.

I'm curious to know if it's a Fuel Pressure Regulator problem. I've read a lot about these failing so that the car is running too fuel rich, and I've even replaced one of mine in a 745T that I suspected of causing a fuel-rich state. What I'm thinking is he could have a problem where the FPR is not closing the return line under load, so he's got no power when hitting the gas under load.

The other thought I've had is the main pump may have failed and he's running on just the in-tank pump.

Once the hose is 'repaired' I'm going to have him listen for the pumps. I'd want to be certain these are making some noise at idle.

What I'd like to know is:

1 - has anyone had a FPR fail and result in this sort of performance problem? Lots of posts in the archive and the FAQ talk about the 'too rich' failure of the FPR. Anyone had a fuel-lean failure thanks to the FPR?

2 - any tests we're leaving out here?

Thanks for any help-
-Dylan