danalex

Sorry if this is the wrong section...couldn't make up my mind.

I've either got a messed up Quadzilla Commander or a messed up RAPTOR 150 fuel pump; I don't know what--only thing I can trace it to might be bad fuel. Issue: Qdzila Commander guage is showing my fuel PSI all over the map between 0 to 18; close your eyes and open 'em and you'll see a different number every time! Seems to have started with the last fill up.

Sunday morning near San Antonio. Outside temp is in low 40's.
I insert the key and turn to "on" position without starting the truck.
FUEL PSI: 0 (I hear the RAPTOR 150 come on, but goes off after a few seconds)

I then start the truck.
FUEL PSI: bounces all over between high of 18, to low of zero. BUT THE TRUCK IDLES PERFECTLY WITHOUT ISSUES.

As I drive the truck, the FUEL PSI reading eventually levels out, fluctuating between 13-16 PSI. When I stop to idle, the PSI fluctuates
between 8-12. BUT THE TRUCK OPERATES WITHOUT ANY ISSUES.

Here's a laundry list of everything I can think of that I've done in the last 2wks, both immediately prior and after the COMMANDER FUEL PSI issue.

--Changed oil about 2500 miles ago.
--Relocated the "puke bottle"
--I filled up with fuel at a place I don't normally get fuel; I've stopped there in the past, but its not my normal station. Took on 25gal.
--At fill up, I added an 11oz can of "BG Diesel Care" to the fuel. I've also done this before and do so periodically for general PM. Have never had issues with BG; product claims "...will not harm plastic components in modern injection pumps and is compatible with catalytic converters, sensors and trap oxidizers."
--Problems with the COMMANDER FUEL PSI reading began just below 1/2 tank of fuel was used.
--Went out of town so I left the truck sat for about a week.
--Temperatures between 70 during the day, lowest was about 30 one night.
--Came home and changed fuel filter (only slightly overdue; about 9K miles since the last); filter appeared dirty, but not too terrible. BUT, the fuel drained from the filter canister was yellow-ish and darker than new fuel. (see photo)
--Drove truck until slightly lower than 1/4 tank; COMMANDER still shows wild PSI readings.
--Checked all the connections for the Quadzilla; all snug.
--Adjusted the RAPTOR pressure setting 1/4 turn higher. Seems to give higher reading on the COMMANDER, but still wildly active...even shows "0" periodically
--Filled tank today.
--The RAPTOR 150 fuel pump seems to be working fine (I hear the whine noise it makes). RAPTOR was installed Oct 08.
--Installed QUADZILLA COMMANDER latest software update 1.14.9

I've ordered a mechanical FUEL pressure tester gauge from Geno's; enroute in the mail; will remove the COMMANDER 'canister' to check the psi with mech. dial gauge vs the COMMANDER digital.

Again, the truck runs/operates just fine...no stalls, no dead peddles, same acceleration, same starting, no knocking, and "computer overhead" shows same MPG as I've always had (18-22)--truck runs great!

BUT I'm concerned with the COMMANDER readings though.

I've contacted QUADZILLA Customer Support...waiting for their reply.
I've shown the phot to Glacier Diesel (where I got the RAPTOR pump); they agree the fuel looks bad...but the truck runs perfectly... QUESTION: If I got a batch of "bad" fuel (not sure what that means) will the truck still run just fine?

Appreciate any additional thoughts or recommendations

Zeus1987

kind of sounds like you have one of those defective fuel pressure senders.

around here your average batch of bad fuel will just make your truck run louder and not get as good mileage. the fuel pressure doesnt really change