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Car runs fine. It does have a problem starting once in a while. I put a gauge on the fuel line. turn the key and have 40 psi right away then it bleeds down to 0. I think I have a bad injector. any thoughts on this would be helpful:huh:
 

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DC Crew
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How long does it take to bleed down to 0? Have you pulled your plugs and looked at them? Surely the one leaking down will have a rich cylinder.
 

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it stays at 40 for about 2 seconds then goes right down to 0
If pressure is dropping that fast most likely either the check valve on the supply line in tank is faulty or the fuel reg is faulty ; both will bleed pressure straight down.
There are tests to do to determine where problem is
As Raid says , a leaking injector would show up as a wet plug and it would be rich out the exhaust
 

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Pull the vac. hose on the fuel press. regulator, cycle the key & look for gas to come out of it.
If its an lt1, its pretty easy to pull the injectors up enough while the fuel lines are still hooked up & cycle the key.
 

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If you want to rule out the regulator, it is pretty simple. Clamp off the return line, pressurize it and see what it does. If pressure still drops, the problem is not in the regulator.
 

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If you want to rule out the regulator, it is pretty simple. Clamp off the return line, pressurize it and see what it does. If pressure still drops, the problem is not in the regulator.
:thumbsup:
Conversely do the same for the supply line
 

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this is what i did to see if it was my fuel pressure regulator , i turned on the car , then went over to the vacuum line attached to the regulator and disconnected it while it was running , and saw that it was spitting out fuel , give that a shot , if not then check your plugs . another way i found out to check for a leaking fuel injector i drove the car for about 15min then came home turned it off took off the rubber tube that goes from the throttle body to the filter , manualy opened the throttle and listened inside the throttle body and i heard dripping and sizzling drip and sizzle , found out that my #1 injector was leaking , just a couple ideas if you dont have the specialized tools .:thumbsup:
 

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El☠Diablo;1849055 said:
this is what i did to see if it was my fuel pressure regulator , i turned on the car , then went over to the vacuum line attached to the regulator and disconnected it while it was running , and saw that it was spitting out fuel , give that a shot , if not then check your plugs . another way i found out to check for a leaking fuel injector i drove the car for about 15min then came home turned it off took off the rubber tube that goes from the throttle body to the filter , manualy opened the throttle and listened inside the throttle body and i heard dripping and sizzling drip and sizzle , found out that my #1 injector was leaking , just a couple ideas if you dont have the specialized tools .:thumbsup:
That would be good for if the regulator diaphragm ruptured. If the spring is weak it will seep off but not show in the tube.
 

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Discussion Starter #12
ok

:WTF I pulled the injectoers out and turned the ignition on. nothing happened. puled the vacumn line of the reg. and turned the ignition on. nothing. seen how I shou;d pinch the fuel line and see if check valvs is bad. how do you pinch the lines?and is thr check valve in the fuel pump
 

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:WTF I pulled the injectoers out and turned the ignition on. nothing happened.

puled the vacumn line of the reg. and turned the ignition on. nothing.

seen how I shou;d pinch the fuel line and see if check valvs is bad. how do you pinch the lines?

and is thr check valve in the fuel pump
You don't crank, it don't spray.

That means the diaphragm is not leaking.

That I am not sure about. It has been so long since I had a stock system, I can't know that. I would suspect that based on what I did not too long ago, there is a return line leading to the fuel tank that is rubber.

IIRC, there is a check valve in the pump. Also there is a pulse dampner that might be leaking. All in the pump area.
 

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there is a return line leading to the fuel tank that is rubber. .
You need to access the two rubber fuel lines , possibly at front of fuel rails or by removing the filler door and rubber boot to get to lines where they enter tank
Pressurize lines ( can put 12V direct to terminal G on ALDL connector , pump will run without key on ) , stop pump and watch gauge to see if pressure changes, then do other line
 

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You need to access the two rubber fuel lines , possibly at front of fuel rails or by removing the filler door and rubber boot to get to lines where they enter tank
Pressurize lines ( can put 12V direct to terminal G on ALDL connector , pump will run without key on ) , stop pump and watch gauge to see if pressure changes, then do other line
I can't be sure. I have rubber fuel lines but I also have a HSR. I don't remember what the stock system was like but thanks for advising him.
 

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I don't remember what the stock system was like
Stock you have the two flex lines at front that come up to the fuel rails but they are hidden under the AIR divertor valve
Accessing the lines at tank is probably easier option

 
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