2003 workhorse P32 fuel pressure

I believe there is a regulator on the rear of the left side fuel rail. Are you having problems? I would think 46 lbs would still be enough for normal operation.

I think it is 56-62 psi, but either way yours is low, I added a fuel pressure gauge to mine as one of the potential disaster failure modes on these engines is low fuel pressure as the ECM assumes you have correct fuel pressure for its fuel injection timing, as there is no fuel pressure sensor, low fuel pressure can therefore cause the engine to go lean and all the bad things that go with it (burned pistons, detonation, etc.) The fuel pressure regulator may be adjustable depending on the year, mine requires a security torx bit (torx screw with a center post) to adjust, though you should first check it by removing the vacuum line from the pressure regulator and see if fuel pressure goes up to the normal range, just be careful as a failed fuel pressure regulator may allow fuel to squirt out the vacuum line.

p.s. confirm with a mechanical fuel gauge, as a bad sensor or even a poor ground can through off the reading on the electronic dash gauge.

60-66 PSI according to the manual I have.

Thanks for the info. I'll look tomorrow for the regulator.

Yes, I have been having trouble. I had trouble with a clogged fuel filter, changing it helped but still have intermittent issues with it loosing power. I step on the gas to accelerate and instead of reving, the engine nearly dies. (No check engine light). I haven't driven it any distance since installing the gauge but I'm curious if I'll see a further drop in fuel pressure when that happens again. I also have a scan gauge conected so maybe that can shed some light as to what's going on.

Thanks
Jason