1985 Ford F-250 “Clyde”

[mack2188]

Hey everyone!!

Sorry, work has been brutal with the heat and I have been meaning to post about my project truck but come home and am exhausted!

I have a 1985 F250. 5.0 v8 efi, 4x4, long bed, regular cab, 4 speed. I have replaced the plugs, solenoid, air filter, alternator and power steering belt, front tank/pump and inline pump. Also had a fight with the front brakes and those are now completely redone as well. Not dialed in just yet but getting there.

Main problem is when I go for a test drive, it’s very sluggish. Granted the exhaust is essentially straight pipe at moment til I can weld a muffler on for some more back pressure, but it struggles to get out of 2 gear. Idles very well, temp is a little misleading but I will be replacing the thermostat and flushing the system soon. I have also put some treatment into the fuel and sea foam in the engine to see if I can breakaway some of the gunk since it’s sat for I’d guess 6-7 years.

Only driven it down the driveway and small back road and back and at most 5 -10 minutes. Time to get to temp and then come back to cool down.

Thinking it may have something to do with injection/exhaust. Thought timing but idle is smooth. Also it still had a smog pump on and it locked up, so it now has been removed and I clamped the hose for the time being til I can climb into the back of the engine bay.

I am no expert so any advice is appreciated. All I’m currently doing is starting it every couple of days, idle for a few minutes and leave it be.

Thanks!!

[Gary Lewis]

These EFI systems are pretty finicky about needing all of the systems working or it goes into limp-home mode.  In that mode the ignition timing is locked and you have just enough power to drive the truck.

My guess is that you have something wrong and the computer has its knickers in a twist.  Have you tried pulling the codes?

[ArdWrknTrk]

Welcome Mack!

I'm going to suggest checking for codes.
With early (OBD1) EFI you can flash out codes on the check engine light by grounding the test connector.
The procedure is here in the documentation.

Just because it isn't on doesn't mean there's nothing amiss.
It truly sounds like the timing is locked or the truck is in limp home mode.

[grumpin]

Welcome!

[ArdWrknTrk]

Ha Gary!
I see we replied at the same time.    


Great minds think alike???    

[Gary Lewis]

Yes, Jim, I'm afraid for your sake that we do think alike.  At least on some points.  

Mack - To pull codes follow the instructions on the page at Documentation/Electrical/Electronic Engine Control (EEC) and then click on the EEC-IV tab and then the Code Checking tab.

[mack2188]

So finally had time to check in on the truck. Bought the cheap OBD 1 code reader at the parts store. Did the process to read codes and got nothing. Ran it multiple times to be sure.

I then discovered what I believe is the spout connector for the timing advance from the computer. I unhooked it, set timing to around 13, and stayed steady. Once I plug in the spout, it throws it out and timing looks to be all over the place (least with the cheap light I have).

Could I need to look at replacing some old engine control connectors? In new territory with this one and has me scratching my head!!

[mack2188]