bigfoot

I need to know what the accepted minimum is for fuel pressure. My truck is stock with gages. Normal idle and unloaded highway PSI is close to 20 PSI, but recently I have noticed when pulling a trailer and accelerating the PSI is dropping to around 10 and sometimes lower. This has been very noticeable when getting on the freeways with a load.

I only have 840000 miles on the truck so warranty is still in effect and replacement should not be an issue I just don’t want to trash my VP44 again.

Also if the pump needs to be replaced are there any “buzz” words I should use to assure that the dealership gets it right.

Patrick Campbell

8 PSI is according to the books absolutely minimum. You should not be seeing 20 PSI at all.... You should be seeing about 15 PSI at idle.... do you have a pusher pump?

KATOOM

I'd say with 840000 miles your far out of the warranty time frame!
And thats right, you shouldnt be getting 20 psi at all with stock LP. Is your gauge right? Maybe you should check that first. The low pressure limit for DC is 7-8 psi at WOT but the trick is it depends on what the dealer considers WOT. Sitting in N with the pedal mashed or driving in gear while the engine is under a load. Obviously the later is the right way to measure but like I said its up to the dealer.

phox_mulder

They now rely on the flow test, so many liters of fuel in 25 seconds, or something like that.
Can't remember the exact specs.


phox

bigfoot

Thanks ya’ll, the gage should be ok but it will be easy to check. I have a 0-60 gage that will do to compare with.

This gage has shown about 20 since the install and that has only been a few months.

As for the 840000 give me a break I got all nervous and hit the 0 one to many time .

Thanks again