Hi guys - I just installed my gauge and isolator, and I'm only reading 6 lbs. at idle during the initial re-start after getting stuff plugged back in - haven't driven it yet - just at idle and then I ran it up to about 2K rpms and the gauge barely moved. Should I be driving it and see how it works after I run it a bit? What should I 'normally' be seeing? Truck is stock other than the gauges. We did bleed the isolator also.... Help ????

 

There have been many folks that installed fuel pressure gauges only to find their lift pumps are either completely toast, or on their way out.
Your pressures should vary between idle, 2000rpm cruise and wide open throttle.
Mine shows 16 idle, 14 cruise, and 10 WOT.
Most agree that any reading below 8 psi is time to start shopping for a replacement.
Look on the bright side, at least you know yours is a problem before the injection pump takes a dirt nap.

 

Could be an isolator problem....you could bypass the isolator and see if you get the same reading

 

It stuck at 6 lbs even when shut off

 

Well, I've only run the truck once now, and only for a couple of miles after all the gauges were installed. It looks like the FP is now reading about 7.5 at idle, about 6 a 2K rpm's, and about 4.5 at WOT.

I thought that these numbers for the 600-610's were about normal.... Anyone agree / disagree? I also realize that the gauge could be slightly off due to the isolator, but I'm not going to run a straight line into the cab. The wife already complains about the smell of the diesel exhaust; if I got diesel fuel in the cab that'd be a whole different kind of pain....

Oh yeah - almost forgot - I also have about 9K miles on the current fuel filter.

Thanks for the input guys....

 

I see a new lift pump in your future.


As for the straight fuel line in the passenger area, mine's been leak free for 3 years+.

 

My suggestion to bypass the isolator was only meant as a temporary test. I guess you can always wait until the injector pump dies....then youll know the problem for sure.

I dont understand how guys can say that running a fuel line to the cab is going to make it smell like diesel??? If it aint leaking - it aint going to smell like diesel.

BTW, leave your lovely wife standing on the side of the road a couple of times - I guarantee she'll quit compalining about "diesel smell" real fast I sure dont envy you married guys.