Dangerously low fuel pressure. HELP!

[Bramma]

Okay so I've been running Corksport's HPFP for about 6 months now and everything was fine. Fuel Pressure was 430 at idle and shoots up well above 1600 when I tap the gas pedal. Suddenly I'm driving last week (under 35mph) and engine suddenly starts bogging out and barely giving power when I press the gas pedal. That was quickly followed by a check engine light. Code was p0303. Misfire in cylinder #3 .

I did the easiest step first, I switched the coil pack from cylinder #1 & #3 to see if that would change the code to cylinder #1 . It did not. So I decided to change my spark plugs to the NGK's that a lot of people here have been raving about. Spark plugs were gapped between .026-.028. Now the code changed from p0303 to p0300 which is random misfires. Car still drives terrible and is now making a clicking/rattling noise when the gas is pressed.

So now I bust out the AP to do an idle log to see if anything seems unusual and suddenly my fuel pressure that was at a perfect 430 prior to this problem is now erratic and struggling to pass 100. So that's when I searched the forum and realized it might be my HPFP. I pulled it off the car to inspect it and it looks in VERY good condition. No damage to it at all. It's currently still out of the car because I want to give it a good cleaning before re-installing it.

Could someone look at my log and tell me if it might be my relief valve or spill valve. Or maybe tell me what failing HPFP internals are supposed to look like? Anything helps because I don't have money to spare right now.

Mods are in signature and Freektune'd.

PS - Prior to this issue, I've noticed that my car has been horrible on gas as well. Burning a half tank of gas in a week to drive about 5-8 miles a day. Not sure if that ties into the problem as well.

[Bramma]

Bump!

[aackthpt]

If you're getting that poor of fuel economy you might be evaporating the gasoline away. Have you inspected under the hood carefully while the engine was running, especially the fuel hardline between the HPFP and rail? Pretty common for that to crack and mist fuel into the engine bay, resulting in low FP, pretty rainbows and eventually a big fireball. Luckily this is an easy fix.

If the car has a rattle when you press the gas, I've heard cars with broken ringlands that sound like that. Pull the plugs and put a borescope down there to inspect the pistons ASAFP. If you caught it early enough fixing this doesn't have to cost a mint but it ain't cheap no matter how you go about it.

[Bramma]

Just a little update. It was the fuel relief valve. Car is back to normal.

[Rotareez]

Glad to see you got the issue fixed! Did you happen to see if you could blow through your failing RV? Reason being, I am having the same issue and have changed everything besides RV.....It passes blow through test and KOEO build pressure too about 1000 PSI then bleeds off from there.

It would be good to know that not EVERY RV that fails allows you to blow through it like a straw.

[Bramma]

Originally Posted by Rotareez Glad to see you got the issue fixed! Did you happen to see if you could blow through your failing RV? Reason being, I am having the same issue and have changed everything besides RV.....It passes blow through test and KOEO build pressure too about 1000 PSI then bleeds off from there. It would be good to know that not EVERY RV that fails allows you to blow through it like a straw.

Yes, I was able to blow right through it like a whistle!