Still starving for fuel

[Ozwynn]

On my F150 I pulled the injectors out, soaked them in a bucket of gumout injector cleaner over night and cleaned them. hooked them up to power to make sure they click. reinstalled with new o-rings, changed the fuel filer and have run 3 tanks through both tanks with lucas fuel system cleaner. I am still starving for fuel like the fuel pumps are not keeping up.

can I blow compressed air back through the fuel line to blow any junk away from the pick up tube or is that a bad idea?

 

[Dirtman]

Yea thats a pretty bad idea... Have you replaced the fuel filter? Are there any codes? What are the fuel trim numbers? What is the fuel pressure at the rail?

 

[alwaysFlOoReD]

Buy or borrow a fuel pressure tester. I just went thru this, my pump would initially put out 40 lbs but fairly quickly drop to below 10lbs. I'd get a few miles down the road then start losing power and die.

 

[Ozwynn]

I replaced the filter yesterday, no check engine light and when I pull the codes with a scanner I dont get anything except an O2 code which I assume is because its running lean. going to pull the spark plugs tomorrow and see just how lean its running.
spent my whole paycheck on brakes and filling the tanks so no money for a fuel pressure gauge until next friday.

 

[Curious Hound]

How old is the truck? Often, there is a filter on the pump suction (commonly called a sock). So you really shouldn't be getting any big trash in the lines that could be removed with compressed air. Does your last call auto parts store have a fuel pressure gauge in their loaner tools inventory?

 

[Ozwynn]

the truck is a '90 with a 5.0L. I dont have the deposit for the fuel pressure gauge until Friday.

 

[Curious Hound]

I've had weeks/months like that. Wish I had better info to fix your problem.

 

[adsm08]

Yeah, never blow compressed air into the fuel tank. It can be unsafe.

 

[Ozwynn]

I'm pretty sure I'm going to have to pull the bed and clean the pre filters and and get the tanks steam cleaned. but it was running perfectly fine on the rear tank until Janurary. now its like the rear tank fuel pump is dying

 

[Dirtman]

O2 codes go with a rich or lean condition. And there are about 50 codes related to the o2 sensors... So that code is important.

 

[pjtoledo]

have you flow tested the system? should be able to divert fuel into a gas can and run the pumps.

 

[Ozwynn]

have you flow tested the system? should be able to divert fuel into a gas can and run the pumps.

I though of this, but I have no idea what the fuel flow should look like if its working correctly

 

[Ozwynn]

O2 codes go with a rich or lean condition. And there are about 50 codes related to the o2 sensors... So that code is important.

50 O2 codes on OBD1?

 

[Dirtman]

Oh nevermind your right.

 

[pjtoledo]

I though of this, but I have no idea what the fuel flow should look like if its working correctly

speculating here,,, if you get a lot of fuel that would mean there are no restrictions in the system. filling a gallon in 5-10 minutes is more than the engine would consume at full power.
if it flows good, then the issue would be maintaining pressure at the flow rate.
is it a circulating or dead head system?