I have a 88 F250 351W that I just can't figure out. It will start and idle but it's strugging to idle and as soon as you give it gas it dies. I can spray starter fluid in it and the idle picks up to where it should be until it burns off the starter fluid. It's like it just isn't getting fuel. I've replaced tank, sending unit, inline pump, fuel filter, plugs, rotor button and cap, and plugs. Took the uel line of from the filter to the ful rails and it is clear of obstructions. Would injectors cause it to do this? Any help would be appreciated.

 

How much fuel pressure are you getting at the motor?

 

Put the gauge on the schrader valve, cycle the key and the gauge doesn't move. I've got under it and can hear both pumps run. The one in the tank and the one on the rail. Took the fuel line lose from the fuel filter and fuel squirts out the filter when the key is cycled.

 

So it's moving fuel but there is no head for it to build pressure against at the motor. Pull the oil dipstick to see if the oil smells like gas or if the level is overfull. If so pull spark plugs to see if they are wet, if they are then one or more injectors is stuck open.. look for shorts in the wiring between the computer and injectors. You could also remove the the vacuum line from the fuel pressure regulator to see if fuel is leaking past the diaphram, if it is replace the regulator. If all that checks out OK(no gas in oil, no wet plugs, FPR not leaking) then you likely have a problem with the dual function resovoir on the frame.

 

Pulled the plugs on passenger side and 2, 3 and 4 are wet. Just some back ground. I bought the truck and drove it for a while then drove it to work and it drove fine, the next morning on the way home from work it started struggling at the least little incline. By the time I got home it was barely able to make it. It was bogging down and popping through the breather. Also when I bleed the schrader valve I get air and sometimes just barely a little bit of fuel but mostly air. And no fuel in the vacuum line from the regulator.

 

Sounds like you have injectors stuck open, have a look for evidence of chewed wires and if you don't see anything disconnect the battery and remove the PCM(in drivers side kick panel), you have to disconnect the wiring harness from under the hood and then go in the cab and remove the plastic kick panel and whatever is holding the PCM in the fender cavity. Open up the PCM and look for corrosion or exploded components, maybe take a pic and post it up if you find anything besides a clean electronic board inside.

 

If it idles as you say then you know you have at least 28-32psi fuel pressure so you are not getting the fuel gauge connected at all if it stays at zero.

Sounds like you may have a bad Throttle Position Sensor (TPS) and you are giving it air when you open the throttle but the TPS is not giving the information that the throttle is open back to the Computer. This would make the mix lean and cause the popping.

What you need to do before throwing parts at it is see what codes you have stored in the the Computer. Also run the KOEO self-test to see if the wiring is OK.

 

I think you're getting false readings from your pressure gauge, I bought one at Autozone and had same issue, pulled that little rubber plug out one end of the Ford adapter (or the gauge hose end, can't remember). The plug keeps the needle from pushing the needle that releases pressure from the rail.

 

Makes sense. I will try to check pressure again using this information. Thanks. Also how do I check codes? And if it is injectors how much am I looking at spending there? This is a farm truck and I really hate to put a bunch of money into it.

 

Free method: Fuel Injection Technical Library » How To Run a Self-Test

Run the Key On Engine Off (KOEO) tests and Continuous Memory (CM) display first. Post the codes by number and when they were displayed here.

If you want to see what the code definitions are look here: Fuel Injection Technical Library » 2 Digit Self-test Codes 11-32

 

Ran KOEO test and the numbers I got were 8-1 8-2 and 8-4 any help here would be great!

 

I have a half ton that was doing this , ended up being and o2 sensor $40 just throwing that out there

 

81
Secondary Air Diverter Circuit Failure

Turbo Boost (2.3L Turbo)

Insufficient IAS Output Voltage Change When Solenoid Is Activated (3.0L SHO)


82
Secondary Air Bypass Circuit Failure

Integrated Relay Control Module (2.3L Turbo)

Supercharger Bypass Circuit Failure (3.8L SC)


84
EGR Valve Position/Pressure Feedback EGR/EGR Control Circuit Failure

 

What does all that mean? Sorry I'm not experienced with this stuff!

 

Me to! Dunno, there is some sort of vacuum valve or solenoid this leads to. From a repair I did a while back on my fuel system I think it's on the frail rail or behind the cab but in front of the fuel tanks. do some googling. May or May not fix your issues.
Hope it helps.

Z