Fuel Pressure Really Low

[Xero_Tolerance]

Does anyone know what would cause my fuel pressure to only get up to 13psi even when I have my afpr set as high as possible? The fuel filter was just replaced and the pump itself turns on instantly. It just started happening randomly one night. It was fine, turned off the car and went into my friend's place for 5 minutes, came out and it was running really lean. Got home, turned it off, turned it back on and it wouldn't even barely run without stalling. Found out the fuel pressure is ridiculously low. Sounds to me like the fuel pump but I've also heard that fuel pumps generally work or they don't. Oh, it's a walbro 255 and I took it out to take a look at it but couldn't really determine anything from looks alone. Are there certain parts on it I should double check? I don't know if it makes a difference but it did get cold recently. Any help would be very much appreciated. Should I just get a new fuel pump?

 

[16gpoweredgsx]

Did you double check your fuel filter for leaks?

 

[turboglenn]

Also, check for any pinched fuel lines on the way from teh pump to the rail. But it sounds like the pump may be going out. Try this, with teh car's fuel pump running ( use teh test lead on the firewall) turn teh adjuster on teh AFPR in and see how much pressure you can make. If it won't go up to at least 70PSI or so, then your pump is probably shot. I can get mine up to damn near 90PSI using this test and i have teh same pump on stock lines from teh tank to the rail

 

[tqmx1]

The other simple one check the plumbing to the guage and the guage. The line could have got pinched or the guage is takeing a dump.

 

[Xero_Tolerance]

The gauge works alright. The fuel filter was just replaced by a shop and the problem was present before and after the change of the fuel filter without any difference. I would think I'd notice a leak because I definitely don't have any puddles under my car and it doesn't smell like gas anywhere. It won't go above 20psi no matter what I do to the afpr. I don't think there are any kinks in the line but what would be the best way to check for that?

 

[turboglenn]

Best way to check for leaks is power up teh pump and start crawling around and looking everywhere with a flashlight. But if you can only manage 20PSI no matter what i'd say your fuel pump is gone south. Even on my stock wired pump ( walbro 255) on stock feed lines i was able to get well over 80PSI at teh regulator by just turning the adjustment rod while the pump was running. But i had to rewire it because i was loosing fuel in teh top RPMs

 

[GS-T_Newboost]

on the bottom of the pump there is a filter. if it is cloged then that would cause low fuel psi.

 

[Xero_Tolerance]

How can I tell if it's clogged? I took it out and it's pretty yellow and a bit grimy. but if i squeeze it then it will squirt out some fuel... I guess I should take a closer look at that.

 

[turboglenn]

How can I tell if it's clogged? I took it out and it's pretty yellow and a bit grimy. but if i squeeze it then it will squirt out some fuel... I guess I should take a closer look at that.

They turn yellow after a while and some are yellow to start with. Blow it clean from teh inside with compressed air to clean it. But normally it takes a LOT of sludge to clog the pump sock ( screen on bottom of pump )

 

[Xero_Tolerance]

Thanks. I'll look into that.

 

[tqmx1]

Check your FPR. I might have got some crap caught under the seat alowing the fuel to bypass. Pull the return line and turn on the pump if it is comming out like a fire hose you found the problem.

 

[Xero_Tolerance]

I took out the fuel pump and the AFPR and now I have the fuel pump with a line going RIGHT to the AFPR and the fuel pump is hooked up to a 12V converter. If I turn it on and the pressure doesn't get over 20psi on the afpr then I know for a fact that it's the fuel pump. My question is... will using water in the fuel pump be a really bad idea? Or would that not hurt the fuel pump. My intuition says if it can handle fuel then water shouldn't be a problem but I'd rather be safe than sorry.

 

[Xero_Tolerance]

Well I figured water won't kill it if it's already dead anyway.... So I hooked it up and it only reaches 13psi. Seems to me like I have a messed up fuel pump. At least the AFPR is working though. Looks like I'll be ordering a new walbro 255. Thanks for your help guys.

 

[Xero_Tolerance]

Anyone know the cheapest place to get a walbro 255? I'm kind of skeptical about using the classifieds and I don't need the kit, just the pump.