[andrew6.0]

I have been going on with low fuel pressure problems for 2 months now. The truck recently had an airdog. My fuel pressure started dropping so I decided to do the blue spring upgrade considering I put a new motor on my airdog about 4 months ago and didn't think it was broke. Blue spring was no fix. I thought maybe my gauge was messed up since I had already bought several sending units for my glowshift. Bought new autometer gauges and still reading low. So finally I dropped everything and ordered a fass with the sump. Had it installed and I'm STILL having the same problems 1000 some dollars later. When I start my truck my fuel pressure is perfect... around 68-70psi. I can drive it for about 10 minutes and the fuel pressure starts dropping. The more I drive it the more it drops. keep in mind I have checked all the fittings and lines and everything is brand new so I'm not pulling air. The guy that installed my airdog seems to think its a bad injector or injector o-ring leaking compression back into the fuel bowl. The truck runs perfect, no excess smoke, no miss or shutter. no white smoke, idles and starts up fine. I am completely stumped here and I'm ready to put this problem behind me. I am looking for any ideas or suggestions before I have the injectors/ O-rings checked. Also I should add that when I prime my fuel bowl with the cap off, within about 5 minutes all the fuel will be drained out. I have no clue where its going. I have checked every nook and cranny and cannot find a single fuel leak and I never smell fuel. Any help whatsoever would be VERY much appreciated. Sorry for such a long post its just been a very nerve racking past few months. And I'm new to forums so if I'm in the wrong place feel free to redirect me.

 

[Ford06]

Could it be something in the tank restricting fuel pickup? You don't state what year your truck is, but some of the earlier ones had a coating in the tank that could break down and plug the pickup. You might drop the tank and check it.

 

[andrew6.0]

Truck is a 2006 and i told my mechanic to check for debris in the tank and make sure it was clean when he drilled the hole for the sump. That's the reason i installed the sump so i could rule out any draw straw problems and make for a much simpler fuel supply