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No fuel pressure

A

Azvforce

Active Member
Had the car at a shop to pull engine and reseal everything. Had them install my new Comp 6262 and a PTC converter as well. He said it was done but seemed like it was running lean. Have a new wideband here at home ready to go in and who knows what fuel pump is in car or how old it is. Car started and drove fine but would break up under any boost. Once home, I check everything over and drive around block to watch scammaster and maybe make some adjustments. I try hitting gas hard and engine dies. Crank no start now, and zero fuel pressure. Doesn't prime either.
Today I install a Racetronix hot wire setup and 255 pump. No fuel pressure still. Checked fuses under left driver side dash and they are all good. Any ideas?
 
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Update. Got car to start. Fuel pump does not prime. Have to crank for 4-5 sec then it comes on. Had stock regulator that was always exactly 40psi. Would stay at about 34psi at idle when getting running today. Swapped on my new Accufab here and had to screw adjuster all the way until it stopped to get to 43ish psi.
Car seems to idle okay and rev up good. When driving, any kind of load it hesitates. I did find that I lose pressure at the rail within 10sec of turning engine off.
Injectors are 60lb from Turbo tweak and have about 300 miles on them since installing them 6mo ago. Car had engine out for a little over 2mo and these problems are since motor going back in. Stuck injector possibly? That would not explain the no fuel pump prime though.
 
Losing fuel pressure at the rail is a problem with the fuel pump. If I recall correctly the pump should have a valve to stop the fuel from draining back and it should hold pressure at the rail. This should not impair the function of the engine while running as the pump is constantly pushing fuel forward, it just makes for long cranking at start up. This said, the pump is likely old and I would replace it with a new one for confidence that pressure is held while in boost, fuel psi should increase 1psi for each psi of boost. Be sure to remove vac line when checking pressure at the rail.
 
Your problem is the Accufab reg, the newer ones will not hold pressure at the rail, BUT it will still work though this is the problem, if your sock falls off the pump you wont know it because the Accufab mimics the same symptom, which is it won't hold pressure.
It will do the same thing if there is no check valve in the pump but that is not a issue with Racetronix pumps, only with the DW400 pumps... My advice would be buy a reg from Kirbans, pull the pump to make sure the sock didn't fall off, remove the Accufab and throw it as far as you can... then pick it up and throw it again...
 
Is there a way I can check it? I had actually bought one a while back but it arrived with one of the pins broke off.
 
You can ohm it out but thats not guaranteed. Test for 11-13 ohms on each coil.
Better off going to auto zone and getting a duralast coil and trying it. You can always return it and i have read good things about the duralast coils.
 
Car starts, idles, and runs good. As soon as boost comes on, it hesitates. If I stay in it, it clears up by 7-8psi and will run awesome up to max boost(17psi) with Scanmaster readings at 830.
 
I would start with getting the wideband installed and powerlogger, tuning with the stock O2 and Scanmaster is super slow and old school.

What injectors and chip are you running? Are you still running stock MAF? Stock MAF reads at part throttle, but then just maxes out early in boost. May also be part throttle tuning.
 
Cam sensor was bad. The shop put in the wrong spark plugs as well. Got it running good on the dyno at 13psi, then the cam sensor failed again.
 
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