Hi All 

I have searched high and low and didnt seem to find anyone with similar issue. Just bought a 2002 6 speed with an edge juice and fass ddrp lift pump rebuilt VP at some point. The issue is sitting overnight it looses prime between vp and injectors. Parked nose downhill so front bumper was a good 2 feet lower than rear. Same thing only low pressure fuel to #4. After muchhhh cranking dribbles at 1 and 3. It will eventually fire up like nothing happened no smoke. pulls hard on road absolutely no drive ability issues fp 13 at cruise on level 3 and 17-18psi idle.

Tried unplugging lift pump to test for bad diaphragm and it still didn't start.

Sits for 2-3 hours and insta fire.

 

Its at the shop now and they tried to start it after sitting overnight and same thing no high pressure at injectors. Fuel at vp inlet no air. They hotwired the vp and instant high pressure fuel at injectors. Plugged harness back into vp and boom insta start. They checked the pin thats not supposed to have any power only after the key goes off and all was fine. No codes either.

Ecm issue ? 

Is it possible sticky rotor in pump and that the power from battery to the vp is stronger then what ecm sends ?

 

Thanks

Edited January 6, 20169 yr by moparguy55

Stopped at the shop last night after work and the old pump was off. I noticed the wire tap connection looked pretty crusty on the old remanned pump hmmm. See what happens i got a good deal on a 1 yr old reman SO pump with receipt. 

Eric at Vulcan does the right deal as far as I'm concerned. I bought his reman VP. When I called the company sticker on the box (I think Industrial Injection) they said no reman pump goes out the door without a new PSG and I think it's called the updated steel sleeve to the timing advance piston.

I did not have the core out of my truck at the time because I wanted to see how long I could go on 2 stroke with the 0216 error code. It took about 4 yrs, several 1400 mile trips each year driving back and forth to Nevada/ Oregon (plenty 2 stroke in ea tank) with the Vulcan reman behind the seat before I got my first hard start. It was the original VP w/ about 80 k miles on it.

Only reason i didnt go with a new Vp is im not 100% convinced its the pump. Got this SO pump with receipt for $400 and no core. Couldnt locate another ECM to test with either. Scrap yards wanted $500 for a ecm and Im leary about sending mine out to be rebuilt as there is no delayed to start light or any other funky issues and above all no codes at all. Strong fuel with no air at the vp inlet but no pressure out of the Vp. Hotwiring it only works in a heated shop not outside. The mecanic was convinced its the VP. Will see as the SO pump is going on today.

Edited January 22, 20169 yr by moparguy55

Just an update incase someone searches this in the future. Replaced the VP with a used SO reman pump and she sat for 2 days outside got down to -25C on saturday. Was -10C this am and fired up 1/4 turn.

I guess was a rare case of a failed VP without any codes.

Thanks all for the support.

Good to hear and see this brought to good conclusion. 

Glad i  have an edge that will get wire tapped. Shes pretty dead past 3rd gear with no chip. Less power than stock under 2000 rpm no smoke.hooked edge back in the obd port. Havent tapped pump yet going to get a cover.didnt really gain any power 7psi boost was all i was seeing. Played with settings and was defaulted to 98-00 changed it to 2002 and picked up some power.Saw 725 egt and 14psi boost. Sounds like a boost leak on intake side of engine.clamps appear all tight. Id say with the 60hp from the juice since its not tapped its probably 20-30hp over the stock 245hp. If i was leaving the truck stock id be disappointed in the so pump on the ho engine.