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1997 not getting fuel/power

2K views 13 replies 7 participants last post by  GAmes 
#1 ·
Let me start by saying I'm not looking for smoke. I am having a problem with my truck and its got me stumped. The was a new truck to me, but it is no means my first rodeo with a ppump. I just recently did 5x14 injectors, 191s, and I pulled the plate out. The truck does not smoke a lick, and it doesn't have the power that it should with those modifications. The truck has a brand new lift pump, new filter, and I double springed my ofv. Just for the hell of it I set the star wheel and pre boost screw all the way forward and still have nothing for power or smoke. I also pulled the fss off and tied it up to see if that was the problem. Is there anything I am missing? I just feel like the truck isn't fueling fully. There are no boost leaks, and it will only pull about 20-23 psi of boost. Is there anything else that could be wrong that would not make it fuel right? Any help is appreciated. Truck also has a 4 inch exhaust, and a built transmission.
 
#3 ·
I'm going to bypass the fuel heater tomorrow to see if it may be clogged. Like I said its got a brand new lift pump, fuel filter, and I modified my overflow valve.
 
#4 ·
I would be checking fuel pressure. If nothing else I would want to know how much pressure you're making with your "double springed" OFV. You can pick up any old gauge for cheap, couple fittings, a needle valve, and some hose for temporary use.

After that, you can try pulling the plate and deleting the AFC foot to ensure those arn't being an issue.
 
#5 ·
with no smoke it has to be a fuel problem. If you have new filters, pump, etc.. I would look for physical obstructions..like mentioned before the pre-screen filter or even the screen on the tank (if there is one)..
 
#6 ·
I'm going to look into it more this weekend. I'm going to pull my AFC back off and make sure I have full rack movement and foot movement. I've also got a needle valve and I plan to check my fuel pressure.
 
#8 ·
Is it possible you might have a blow diaphragm or a broken boost line going to the AFC.
Therefor the AFC isn't moving in relation to boost?
 
#9 ·
The AFC reference line looks good, and the fss is fully functional. I'm going to pull the AFC off too and manually actuate it with my air compressor to make sure its working.
 
#10 · (Edited)
Update on the situation. I bypassed the fuel heater assembly and everything seems to be working properly now. Its pulling Rpms better and the truck will boost to 45psi. I didn't take the fuel heater apart, but I'm assuming its pretty gummed up.
 
#11 ·
I didn't take the fuel heater apart, but I'm assuming its pretty gummed up.
The fuel heater is not the pre-filter screen. You can remove the heater and retain the screen, as in the writeup by Joe G that you were furnished.
 
#12 ·
I realize that the fuel heater and the fuel bowl/prescreen are two separate things. I just cut the hard fuel line, switched the fitting on the lift pump, and added a fuel hose to bypass the whole assembly. Its known to leak anyway, and the heater is really of no use since there is almost a half gallon of fuel between the heater and the injectors. Moral of the story is I didn't bother taking the per screen out. I just bypassed it and the truck has better power and it runs like it should with the mods it has.
 
#13 ·
The part that is known to leak is the fuel heater its self, so far I've never heard of the rest being a problem. What I believe GAmes was getting at is that now you don't have any type of filter before you're lift pump, so anything that can fit in the pickup tube, will try and go though it.
 
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