fuel pump issue

[jayh007]

I installed a Novi 1200SL supercharger in a 2007. I purchased used off a forum member. It came with a S&H modified GT Hat with 405 Walbro Pump and S&H wire kit. After the install, I took the car for a few runs. The Data logs showed the FP duty cycle was around .1-.2 and fuel pressure greater than 39 psi on all the runs. Car ran good. Last weekend I took it for another Data log run and the FP duty cycle was around .5 and pressure around 32 psi. It seems the FP ACT voltage jumped up from around 4 to 16v.
I did a search on the forum, and I pulled the pump, and the hoses and parts seemed ok. Next I checked the wiring no blown fuses or bad connections. I’m kind of new at this wrenched mostly on carbs and spec pinto engines.
I’m open to any other suggestions otherwise my only option is to change the pump.

 

[JeremyH]

Is it tuned? Is the wiring upgrade in and wired up correct? Replaced fuel filter?If the pump is getting full voltage put pressure isn't where it should be. Check the hose and clamps between the pump and factory T on the hat. Also ensure the small screw that holds the wire for the level sender at the bottom isn't touching the housing on the pump on the inside,ie screwed into far.

 

[jayh007]

Is it tuned? Is the wiring upgrade in and wired up correct? Replaced fuel filter?If the pump is getting full voltage put pressure isn't where it should be. Check the hose and clamps between the pump and factory T on the hat. Also ensure the small screw that holds the wire for the level sender at the bottom isn't touching the housing on the pump on the inside,ie screwed into far.

Yes working with Lito with the tune. I checked the wiring upgrade that's OK. I will try the filter but the tank looks spotless ( only 5000 miles on the car).

I will pull the pump again this weekend again ( I HATE re-installing that the locking nut). Just seems weird that it work fine one weekend and the next I have this problem.

 

[JeremyH]

Sounds like a leak or issue with the pump. From my experience 9 times out of 10 its not the pump.

 

[jayh007]

Should have listen to the experts thanks Jermey and Lito it was the hose coming off the pump, had a tear in it. Thanks for the help

 

[JeremyH]