Fuel Pressure issue
Thread Starter
Drifting
Joined: Feb 2009
Posts: 1,408
Likes: 0
From: Hoffman Estates Illinois
Fuel Pressure issue
i posted up this issue a lil while ago and since have just changed out the Fuel pressure sending unit for my pillar gauge..i turned the key to ON and the gauge read about 63..when i started it..it read back up to 75area..
i know the pressure is suppose to be at 59-60. so i talked to my friend that's a certified FORD mechanic and he asked if the fuel system is a return type system or a non-return type system and said if its non return the PCM may be commanding more fuel to compensate for the increased airflow which i have full exhaust and vararam intake with no tune cept a little tweak from a HPtuners.
said If its return style..maybe the regulator is blocking too much to return to the tank...i am unaware what style system this is.
any help would be great!
i know the pressure is suppose to be at 59-60. so i talked to my friend that's a certified FORD mechanic and he asked if the fuel system is a return type system or a non-return type system and said if its non return the PCM may be commanding more fuel to compensate for the increased airflow which i have full exhaust and vararam intake with no tune cept a little tweak from a HPtuners.
said If its return style..maybe the regulator is blocking too much to return to the tank...i am unaware what style system this is.
any help would be great!
Pro
Joined: Aug 2010
Posts: 545
Likes: 4
From: Calgary Alberta
The PCM turns the fuel pump off and on. It does not control the pressure by servo control of the motor. There is a regulator in the fuel pump itself in the tank. The reason systems have gone away from the return lines, as I understand it, is to prevent heating up the fuel. If you think about it pumping cool fuel up to the hot engine past the even hotter exhaust system and then dumping it back into the tank will raise the fuel temperature. Heat is not something you want to add to the fuel or air entering your engine. I expect evaporative emissions likely played a part in all this as well.
Ditto on measuring, on a temporary basis the fuel with a mechanical gauge. Maybe tape it to the bottom of the windshield and take a test drive. For no reason should it be brought into the passenger compartment. If you can't see/read it through the windshield you probably shouldn't be driving.
Ditto on measuring, on a temporary basis the fuel with a mechanical gauge. Maybe tape it to the bottom of the windshield and take a test drive. For no reason should it be brought into the passenger compartment. If you can't see/read it through the windshield you probably shouldn't be driving.
Thread Starter
Drifting
Joined: Feb 2009
Posts: 1,408
Likes: 0
From: Hoffman Estates Illinois
The PCM turns the fuel pump off and on. It does not control the pressure by servo control of the motor. There is a regulator in the fuel pump itself in the tank. The reason systems have gone away from the return lines, as I understand it, is to prevent heating up the fuel. If you think about it pumping cool fuel up to the hot engine past the even hotter exhaust system and then dumping it back into the tank will raise the fuel temperature. Heat is not something you want to add to the fuel or air entering your engine. I expect evaporative emissions likely played a part in all this as well.
Ditto on measuring, on a temporary basis the fuel with a mechanical gauge. Maybe tape it to the bottom of the windshield and take a test drive. For no reason should it be brought into the passenger compartment. If you can't see/read it through the windshield you probably shouldn't be driving.
Ditto on measuring, on a temporary basis the fuel with a mechanical gauge. Maybe tape it to the bottom of the windshield and take a test drive. For no reason should it be brought into the passenger compartment. If you can't see/read it through the windshield you probably shouldn't be driving.so do you think this can be a restrictive regulator issue? if indeed the fuel pressure is too high from the rail
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Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
Thread Starter
Drifting
Joined: Feb 2009
Posts: 1,408
Likes: 0
From: Hoffman Estates Illinois
well this is what my fuel rail looks like right now..it was a PITA! to replace that sender without it leaking..the easiest thing to get off is the FPSS,, so i'll go to autozone tomorrow and get a gauge.
it won't be like this for long, i'm gonna order the brackets that mount the solenoids on top of the intake manifold. pic was taken during installation, pardon the mess
it won't be like this for long, i'm gonna order the brackets that mount the solenoids on top of the intake manifold. pic was taken during installation, pardon the mess
Last edited by Badd LS6; Jul 14, 2011 at 02:06 AM.
Tech Contributor
Joined: Jan 2007
Posts: 19,401
Likes: 1,144
From: Dyer, IN
well this is what my fuel rail looks like right now..it was a PITA! to replace that sender without it leaking..the easiest thing to get off is the FPSS,, so i'll go to autozone tomorrow and get a gauge.
it won't be like this for long, i'm gonna order the brackets that mount the solenoids on top of the intake manifold. pic was taken during installation, pardon the mess
it won't be like this for long, i'm gonna order the brackets that mount the solenoids on top of the intake manifold. pic was taken during installation, pardon the mess
Yikes......what a mess. I hope you didn't pay someone to do that.....
Thread Starter
Drifting
Joined: Feb 2009
Posts: 1,408
Likes: 0
From: Hoffman Estates Illinois