ryan_289

Stock 2002 24 valve dodge 2500 4wd. Replaced block lift pump with another stock style block pump in May. This pump supposedly has bypass valves in it to prevent injection pump failure if the lift pump goes out. According to the specs it should be b/t 10-15 at idle but there is no minimum for WOT. It claimed that the pressure specs would be more like the newer style "in tank" pumps. At idle mine is usually just over 10, under load usually would drop no more than 5. Last night I get in and crank it up and its idleing around 4-5 psi. Thing is it doesnt move much as I accelerate. It normally would drop as I accelerated. At WOT I can get it to drop maybe 1 psi. So I figure I have one of three things wrong.

1. Bad lift pump. AGAIN.
2. Need a new filter. (could a dirty filter cause this?)
3. Bad gauge?

rich

try replacing the filter first, then check the gauge

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SIX IN A ROW BUILT TO TOW,CUZ WELL WE ALL KNOW , HAVING A V-8 AIN'T THAT GREAT Dodge trucks that havent made life expectancy
96 3500,-175k 98.5 3500 -164k ,98.5 3500-275k, 01 3500-140k, 03 3500 -155k, 07 3500-68k waiting for possible P-Pump conversion and now I'm killing the 06,3500-116k as of 10-01-09 and counting and yes i make my trucks earn a living buy towing professionally

ryan_289

How would I check my gauge? It is an Isspro mechanical gauge with a fuel block valve in the engine compartment.

Dr. Evil

Use another guage. It doesnt have to be for fuel - any pressure guage will work.

This is the easiest place to start.

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It's Dr. Evil - I didnt spend 6 frickin' years in Evil medical school to be called Mr. Evil - Thank you very m-u-c-h!


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THE REAL DR. EVIL

ryan_289

Well its not the fuel filter. Ill have to put another gauge on it Monday when I get back too work. This sucks b/c im leaving out here in a couple of hours pulling a 28' stock trailer about 220 miles. Hauling back about 15000 pounds of cattle. Dont have any other truck to take. Ive got fuel pressure and the truck feels like it has power so I should be fine.

leonesm

Could it be that the fuel pressure isolator is leaking? I had mine do the same thing and traced it to the isolater

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2003 3500 H0 2WD, SRW, SB, 6-Speed, SBC Con OFE, BD Short Throw Kit, Bully Dog Power Pup, Quad X2 Race, Isspro Gauges, 75hp Injectors, GFS 392, Electric Fans, 2 1/2" Leveling Kit, S&B Intake, MBRP 4" Exhaust, 315/70/17 BFGs, Power Wagon Flares, Firestone Ride Rites & Compressor, 12" Center Console Sub

Dr. Evil

He didnt say if he was using an isolator

johnh

you don't say if the gauge is electric or mechanical, but i'll bet it's electrical. and i'll bet that's the problem

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01 3500 ho 2WD;4 inch exhaust bully dog stage 3 inj edge comp(removed hybrid hx 35/40 8/25/04) dyno 419.2 hp 891.8.torque w/stage 2`s on a dyno jet 6/25/03 ,htb2 turbo installed 8/25/04, not a dually any more,conversion done in 04... added home designed propane march 07 (to improve mileage) new vp 44 from industrial injection 3/july/07 181000 miles, removed stage 3 injectors ,reinstalled stage 2 to try to control EGT's better

Busboy

He does say it's mechanical and I'll bet the fuel block vlv is an isolator. It could be he's lost some antifreeze from the isolator to the gauge. Happened to my father in-law. He topped it up and tightened the fittings it's been good for almost 2 years.

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2001 2500 quad 4X4 5 spd Stock except gauges

ryan_289

It is the gauge. We hooked up another gauge and its reading normal. Pulled my mechanical gauge out of the pod and saw a little drop of antifreeze at the fitting. I guess I need to unhook the line at the isolater and make sure the diaphram is pushed the right way and fill up the line again.