When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
1997 superduty dump truck with 7.3 turbo, auto, 186K miles.
The truck sits a lot. Starts well, no smoke, but the last few times out the truck has been very weak.
Seems like a fuel issue. When warm I'm getting fuel pressure of 10 psi at idle and 18 psi at 2000 rpm which I know it too low.
I have pulled the fuel pickups from both tanks and replaced the in tank screens (no in-tank filters in my 97) and cleaned everything. The tanks and pickups were not really dirty.
How do I tell if the problem is the fuel pump or the regulator? The pressure drops to 0 immediately when turned off. Does that mean there is a regulator leak?
If its not leaking externally anywhere then my bet is on the pump. The regulator is just a spring and valve/seat. Not that the regulator can't go bad but its much more likely a pump issue.