After every hard run with my Comp box on 5x5 or any higher settings, when I come to an idle, my truck is stumbling and idling terrible. Does anyone know why this is?? I have excellent fuel pressures at all times!! Idle : 21 psi and WOT : 7 psi... Is it poor injector's miss or is it my vp 44??? Also when you drive it hard, it sounds like something is hammering (fuel wise). Motor oil is clean and is in great shape.. Anyone out there know????

 

anybody????

 

I think it's because you have a HO. Mine does not idle as cleanly as the SO's. Mine may have gotten worse after adding in line pusher, can't remember when it seemed to get worse, but I've added so many things, it did seem to get rougher over time. Maybe it is the higher fuel pressure? I have 28 idle and 20 or so WOT.

 

mine does the same i think it might be my fass 21psi at idle and 18 at wot

 

My 98.5 did the same thing with all 3 of the VPs it had
Sometimes it would even stall if I got out of it to hard after to long of a WOT pull. Perhaps its just to loaded up with fuel, dont know? I dont think it had anything to do with my fuel system because it did it with stock/ pusher/ FASS?

 

Yeah, very weird. I'm lost!!!

 

You are @ 21 PSI and can drop it to 7 PSI with a FASS? Something aint right there....i got guys with almost 600 RWHP with a 95 GPH at 15 PSI. They can only yank it down to 13.5.....might look for some restrictions.....

You want to lower your Fass pressure, pull the return by-pass spring out of the FASS base plate. I was @ 21 psi....i cut mine a full turn. It droped to 18 PSI. You can play with it from there. Better little less than too much. Put cut end twards fitting, not ball.

 

Just a guess... but the hammering sound could be VP-44 acting up. Checked for any codes?

Failing VP-44 would not explain LOW FP at WOT. Sounds like some kind of restriction in the FASS or fuel line is causing poor running VP-44?? Have seen kink in newly installed fuel line cause very strange problems. Guessing again.

Did you also expirience this before getting the FASS?

When running hard, how does it feel?

RJ

 

No codes found. I had a BD pusher pump before and it was higher at pressures but never had this problem or hammering sound... No kinks in my line, everything look good. The way my duals smoke, I'm guessing I have plenty of fuel. Could it be poor injectors?? These injectors have 160,000 km on them!!!! I'm guessing it's the VP..

 

Anymore thoughts????