Engine/Transmission (1998.5 - 2002) Commander fuel pressure

[Uncle Dim]

Just installed a commander with the FP add on from Quadzilla. FP reads 9psi at idle and drop to 0 at WOT. I didn't install the gauge in the recommended location on the lift pump. Instead I put it on the inlet to the VP44. After much searching and reading either my LP is a POS or my gauge location is causing bad FP readings. I will hoping be putting on my FASS this weekend and that is why I didn't put the gauge on the LP.



Any ideas? Do i just need to isolate the FP gauge from the VP or do I have real problems. Truck runs great and has not given me any issues other than lower than expected fuel economy.

 

[Wyomingcowboy]

I have had absolutely no luck with the fuel pressure sending units from quad. The sent me a brand new "heavy duty" one that i will install this weekend. (PN 102222) I have installed 3 of the previous ones and NEVER ONCE had a fuel pressure reading of any kind. This is the last chance for Quad and me. I hope You have better luck than me! Actually, since you are getting something other than a big fat 0, you already have had better luck than me!

 

[lgill]

I am elated to see I am not alone on this.

I installed the lift pump relocation kit from Genoes Garage at the same time I installed the Quad Commander. I installed the sending unit on the lift pump. At idle I get a solid 12 to 13 psi, but at speed I get anywhere from 2 to 10 with the #'s flashing wildly between these extremes which causes me much anguish as it gives

me visions of chewing up the VP44. I suspected a bad guage as the truck runs great with no loss of power, but can not ignore the guage. Thanks for the input and I have an issue with Quad, ... LT

 

[CKelley1]

the pulsations of the pumps are tearing the sending units up get a 6' plastic oil sending gauge kit add a snubber to it and mount the sending unit leave the tube coiled up and run a ground wire to the sender leave the fitting on the vp44 this also shows filter restriction

 

[lgill]

Thanks for the input CKelly1; I have the sending unit off and am heading to NAPA in search of an oil pressure guage kit and snubber. Do you reccomend a particular snubber? How did you mount the ground wire to the sending unit? How did you mount the sending unit? I am sure you did not let it dangle by the plastic hose.

Thanks again; ... LGill

 

[CKelley1]

i bought the snubber from granger but diesel manor and others have them i mounted mine temporary with a piece of tie wire on the dip stick i used a 16 gauge wire from the sender to a ground i measured the resistance of a new one and it reads about 200 ohms and resistance drops with pressure at 10 psi i was about 130 ohms i now can read the transducer and see if it is bad or use a reostat to check the quad. my spell check says i do not know what reostat is but put a resistor in place of the transducer or sender and you should see a reading