Fuel pressure issues. LT1
#1
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Fuel pressure issues. LT1
1997 camaro z28 6 speed.
Somewhere, the car is losing fuel pressure, very quickly.
41-47 psi is about where it should hold*as per shoebox's website* with the pump primed, ignition on, car not running.
I prime my pump, i get nothing. I prime my pump 6 times, i get 7 psi roughly.
I attempt to start the car, it takes ALOT of cranking, eventually the needle starts to go up as it builds pressure SLOWLY and then it fires. Jumps around from 10-25 psi while the car coughs and almost dies out, then eventually goes to and holds 45psi at idle(This is normal pressure at idle at least lol). Revving the motor yeilds a 2-3psi drop in pressure with no load on it. At WOT the pressure should be again around 41-47 psi. Mine drops to 28 psi and holds there roughly.
When i shut the car off, the pressure drops almost instantly. Doesnt hold any pressure. Also a few times i could hear a hissing noise at the back of the car by the tank. So i have a feeling something is amiss here. Either the pump is going bad, or i have a leak in the line somewhere. Which im assuming as of the hissing noise. So first thing is first, im going to change the fuel filter. Then do a retest and go from there.
Opinions welcome, thanks
P.S What kind of drop in power can be expected with a 15-18 psi drop in pressure?
Somewhere, the car is losing fuel pressure, very quickly.
41-47 psi is about where it should hold*as per shoebox's website* with the pump primed, ignition on, car not running.
I prime my pump, i get nothing. I prime my pump 6 times, i get 7 psi roughly.
I attempt to start the car, it takes ALOT of cranking, eventually the needle starts to go up as it builds pressure SLOWLY and then it fires. Jumps around from 10-25 psi while the car coughs and almost dies out, then eventually goes to and holds 45psi at idle(This is normal pressure at idle at least lol). Revving the motor yeilds a 2-3psi drop in pressure with no load on it. At WOT the pressure should be again around 41-47 psi. Mine drops to 28 psi and holds there roughly.
When i shut the car off, the pressure drops almost instantly. Doesnt hold any pressure. Also a few times i could hear a hissing noise at the back of the car by the tank. So i have a feeling something is amiss here. Either the pump is going bad, or i have a leak in the line somewhere. Which im assuming as of the hissing noise. So first thing is first, im going to change the fuel filter. Then do a retest and go from there.
Opinions welcome, thanks
P.S What kind of drop in power can be expected with a 15-18 psi drop in pressure?
#3
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I ordered the racetronix pump kit from there website. Theres no way in hell its leaking down that fast through injectors, theres no leaks on the ground.Fuel filter wouldnt make it not hold pressure unless it was leaking in which case it would be on the ground.
Ordered the pump and wiring upgrade and will replace the fuel filter at the same time. Going in through the trap door method
Ordered the pump and wiring upgrade and will replace the fuel filter at the same time. Going in through the trap door method
#4
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I ordered the racetronix pump kit from there website. Theres no way in hell its leaking down that fast through injectors, theres no leaks on the ground.Fuel filter wouldnt make it not hold pressure unless it was leaking in which case it would be on the ground.
Ordered the pump and wiring upgrade and will replace the fuel filter at the same time. Going in through the trap door method
Ordered the pump and wiring upgrade and will replace the fuel filter at the same time. Going in through the trap door method
#7
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Two options:
Option A
Dropping the tank:
https://ls1tech.com/forums/fueling-injection/938621-fuel-pump-dropping-tank-write-up.html
Option B
Trap door method:
http://www.geocities.com/formulapower2/fuelpump.html
Here's a thread debating the two:
https://ls1tech.com/forums/showthrea...thod+trap+door
Option A
Dropping the tank:
https://ls1tech.com/forums/fueling-injection/938621-fuel-pump-dropping-tank-write-up.html
Option B
Trap door method:
http://www.geocities.com/formulapower2/fuelpump.html
Here's a thread debating the two:
https://ls1tech.com/forums/showthrea...thod+trap+door