Join Date: Jun 2011
Location: Hamilton, Ontario, Canada
engine can't be revved up
Helping a fellow Alfisti with his 86 Veloce.
He drove it somewhere, parked it and then couldn't get it to restart and hour later.
It had spark, so we started chasing fuel.
Fuel relay, inline fuse, flywheel sensors, battery voltage - all good.
I became convinced it had to be the fuel pressure regulator, so I started to pinch the return line and was able to get it to start and run for a few seconds. I gave him an old spare from a parts car, it got installed and now the car starts and idles, however the engine can't be revved much (maybe to 1500 or so) without getting rough and dying.
I can hear and feel the main pump running, I can hear and feel the in-tank one running, and we pulled it for good measure, and the tank is clean and the stepped hose is intact. Not sure if the sock filter was attached as they tend to fall off as you pull the intank pump. The fuel filter was replaced last year.
I cannot find any vacuum leaks.
At this point, I have a question... can a fuel pressure regulator fail in such a way that it can build up the necessary pressure at idle and not when there is a higher demand for fuel? I tried pinching the return line a bit but it didn't seem to make much difference.
Last edited by mcola; 05-22-2017 at 03:27 PM.