fuel issue. HELP!
fuel issue. HELP! The car has been having increasingly rough starts over the past few months. At this point, the car will not turn over on its own. It just cranks. I know I am getting spark. The car will turn over if I spray the intake elbow with starter fluid, and then the car runs fine.
I measured fuel pressure at the schrader valve when the car is priming and its barely anything. I know the pump is priming because i can hear it, and i know the pump works because the car runs fine once its actually started. Fuel pressure is fine once car is running.
This lead me to believe that when the car is being primied it doesn't have enough fuel to maintain the initial pressure required for starting. Because the priming spray only last for about 2 seconds, i believed that one of the hoses was bleeding back into the fuel tank. But once the car is running fine, the ECU tells it to maintain sending fuel and it can overcome the small leak?
Today, I pulled the pump out and all the hoses look to be in great shape. Can anyone provide a diagram of how the hoses are supposed to be oriented in the tank? Does anyone have any other thoughts on what my issue could be. Again the issue is starting the car, but once running, it runs like a champ.??
I measured fuel pressure at the schrader valve when the car is priming and its barely anything. I know the pump is priming because i can hear it, and i know the pump works because the car runs fine once its actually started. Fuel pressure is fine once car is running.
This lead me to believe that when the car is being primied it doesn't have enough fuel to maintain the initial pressure required for starting. Because the priming spray only last for about 2 seconds, i believed that one of the hoses was bleeding back into the fuel tank. But once the car is running fine, the ECU tells it to maintain sending fuel and it can overcome the small leak?
Today, I pulled the pump out and all the hoses look to be in great shape. Can anyone provide a diagram of how the hoses are supposed to be oriented in the tank? Does anyone have any other thoughts on what my issue could be. Again the issue is starting the car, but once running, it runs like a champ.??
You say it runs fine once started, but does it ever act like it wants to cut out at stops? (i.e. waiting for a light and stumbles a bit when you take off, then comes back normal)
Nope, runs like a champ, no stutters. Which leads me to believe the regulator is fine because i know that maintains pressure once the car is running. I pulled the vacuum hose of when the car was running and no fuel came out, so i think the regulator is good.
Did the pressure go up a few psi with the regulator vacuum hose off (i.e. 45 to 49 psi)? I think your next step would be to follow your fuel lines and inspect for leaks. It is also possible to have a leaking fuel injector. You'd have to pull up the whole fuel rail + injectors to test that.
It is most likely the ball check valve in your fuel pump. If it is contaminated and has a bad seal than pressure will be lost and fuel will drain back into the tank. I had the same problem in my car and i replaced the pump and it was fixed. I'd recommend the granetelli motorsport kit, $125 and has a Walbro pump.
For now you can cycle the key on/off to run the pump a few times before you start it to build up pressure. So turn key to on for 2 seconds, then off, and immediately on for 2 seconds, than off, etc... then start car.
It is most likely the ball check valve in your fuel pump. If it is contaminated and has a bad seal than pressure will be lost and fuel will drain back into the tank. I had the same problem in my car and i replaced the pump and it was fixed. I'd recommend the granetelli motorsport kit, $125 and has a Walbro pump.
For now you can cycle the key on/off to run the pump a few times before you start it to build up pressure. So turn key to on for 2 seconds, then off, and immediately on for 2 seconds, than off, etc... then start car.
ok, i suppose it would make sense to replace the pump first. So i'll buy a racetronix kit. I dont really know how to pull the injectors etc and test for all that, so ill try the pump first since that should be an easy job.
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It's only an easy job if you plan on cutting the hatch. Even then, removing the pump and installing a new one isn't very straightforward. Dropping the tank to replace the pump is very labor-intensive.
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Verdad Gallardo ive already cut the trap door 
..thats how i knew the hoses weren;t cracked because i pulled the assembly out.
However, my question is which pump do i need to get and does anyone have instructions for swapping them? I was going to order off thunder racing. which should i buy? this will only be a bolt on car.
http://www.thunderracing.com/shop-by.../Fuel-Systems/
..thats how i knew the hoses weren;t cracked because i pulled the assembly out. However, my question is which pump do i need to get and does anyone have instructions for swapping them? I was going to order off thunder racing. which should i buy? this will only be a bolt on car.
http://www.thunderracing.com/shop-by.../Fuel-Systems/
so just get this kit? no need for the upgrades right?
http://www.racetronix.biz/customkiti...c=RFPK-003&eq=
http://www.racetronix.biz/customkiti...c=RFPK-003&eq=
