I got another F-150 project. It's a 1985 5.0 EFI. I'm not familiar with the EFI. The engine is giving me fits. When I bought it, it drove home just fine but when I filled the gas tank and the weather got down to freezing last winter and now even though it's summer it will only start if I push the gas down three or more times and hold it to the floor. It won't run unless I keep it at half or more throttle.

I changed the fuel filter, the idle air control valve and the throttle position sensor. Still acting the same. Any direction from anybody?

 

Sounds like it's getting too much fuel. Pull the vacuum line off the fuel regulator and see if it's got gas in it. You also need to pull the codes, here's how to do it.

EEC IV Self Test hookup

 

I will give that a try. Thank you so much. Kevin

 

I recommend you add some ISO HEET to mitigate the effects of the old ethanol fuel now in your tank/s.

https://www.walmart.com/ip/ISO-HEET-...8aAtf6EALw_wcB

I suggest you keep your tank/s as empty as possible unless you are using the truck regularly.

Personally, I would suck it all out and add a gallon or two of 93 octane while troubleshooting.

 

Ohhh, yeah. Excellent idea. Thank you!