Fuel Relaited problem s/c or at least i think
11-25-2007, 10:51 PM
#1
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Fuel Relaited problem s/c or at least i think
When i first go to start the car on a cold morning, it cranks a few times more then norman,but if i turn the key say 2 times and wait a few seconds it starts right up. once its warm i just start it like normal...
i have heard of a few things espacially on supercharged cars and that is the fuel pressure regulator on the fuel rail going bad, it only did this once it was s/c or perhaps could my fuel pump be shatting the bed...
also something else when its cold i have to give it a tad bit of gas once its started for a few seconds to keep it from dieing, again im thinking a fuel delivery problem...once the cars started it runs fine / idles fine and everything in between.
v581
i have heard of a few things espacially on supercharged cars and that is the fuel pressure regulator on the fuel rail going bad, it only did this once it was s/c or perhaps could my fuel pump be shatting the bed...
also something else when its cold i have to give it a tad bit of gas once its started for a few seconds to keep it from dieing, again im thinking a fuel delivery problem...once the cars started it runs fine / idles fine and everything in between.
v581
11-26-2007, 09:04 PM
#5
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RE: Fuel Relaited problem s/c or at least i think
the injectors are new 42's
umm its the stock pump with a boost a pump...im thinking this could have a bit to do with it? its wired on all the time instead of the vaccume switch (KB recommended)
im planning on a coby tank swap with 2 svt focus pumps when i find a deal so i can run 14lbs of boost and not run outta the go juice :P
umm its the stock pump with a boost a pump...im thinking this could have a bit to do with it? its wired on all the time instead of the vaccume switch (KB recommended)
im planning on a coby tank swap with 2 svt focus pumps when i find a deal so i can run 14lbs of boost and not run outta the go juice :P
11-26-2007, 09:36 PM
#6
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RE: Fuel Relaited problem s/c or at least i think
Just because the injectors are new doesnt mean they cant be bad. I had a buddy that put in a brand new ford gt pump that lasted about 60 miles.
The fuel system holds pressure in the line after the car is off. That is why it is so easy to start a fuel injected car. You have a leak somewhere that is why when you go to start it it wont untill pressure is built back up.
The fuel system holds pressure in the line after the car is off. That is why it is so easy to start a fuel injected car. You have a leak somewhere that is why when you go to start it it wont untill pressure is built back up.
11-26-2007, 10:13 PM
#7
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RE: Fuel Relaited problem s/c or at least i think
any clue why it starts right up after sitting for say 4 hours? when the motor is partly warm....hmm leaky injectors that would make me not happy at all...could it be a bad fuel pump or pressure regulator i hear on s/c car they go bad all the time.
11-27-2007, 09:35 AM
#8
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RE: Fuel Relaited problem s/c or at least i think
Your pressure regulater only regulates the pressure coming in to the fuel rail or out of the rail,the fuel pump has a one way valve sort of, and thats what holds pressure at the rail.
11-27-2007, 03:41 PM
#10
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RE: Fuel Relaited problem s/c or at least i think
You really need to learn about the fuel system in your car.98sn95 is correct. The fuel pump has a check valve in it and only lets fuel run one way. The return style system sends the unused fuel back the the tank thru a different line (return line). The returnless system has a fuel pressure sensor that senses how much fuel pressure is in the rails and sends that to the computer which takes that info and info sent from the TPS and MAF and increases voltage to the fuel pump as needed to keep the proper fuel pressure in the rail.
The only way for you to know for sure what is wrong with your car is to get a fuel pressure guage and hook it into the line. The system will hold pressure after the key is off but not forever. You will have to look that rate up yourself. With the key on engine off it will tell you if your pump is working correctly or not but again you have to look up and see what the recommended fuel presure is for your application. If you have 42lb injectors it should be about 40lbs.
I just went back and reread your posts. LOL stock pump with a boost a pump. A tuner let you leave the shop like that. Your pump is probably burnt up. Your lucky your engine hasnst exploded yet.
The only way for you to know for sure what is wrong with your car is to get a fuel pressure guage and hook it into the line. The system will hold pressure after the key is off but not forever. You will have to look that rate up yourself. With the key on engine off it will tell you if your pump is working correctly or not but again you have to look up and see what the recommended fuel presure is for your application. If you have 42lb injectors it should be about 40lbs.
I just went back and reread your posts. LOL stock pump with a boost a pump. A tuner let you leave the shop like that. Your pump is probably burnt up. Your lucky your engine hasnst exploded yet.