Truck is a 1989 F-250 Club Cab 460 EFI with 4EOD transmission originally sold in California.

Hot, warm, or cold doesn't matter, the truck will randomly stutter on take off and if I don't feather the pedal it will stall. It may go days without doing it, and some days it will do it at every stop. Idles great, no obvious missing.

The truck pulls like a mule, but even with the low gears, I don't think it accelerates at full throttle like a 460 should and it will also randomly not go into reverse, will just sit there and eventually start moving.

Don't know if it's relevant but coming to OK from CA pulling a trailer, in New Mexico, I stopped and filled up both tanks and about 30 miles later the rear tank was empty (gauge never worked on rear tank, just ran until it ran out of fuel and switched over.) but when I stopped for fuel later it was still full. Figured I lost the rear pump and haven't used it since.

So far the only thing I changed was the inline fuel filter. The tank switch does not have the removable cup with a filter. Checked fuel pressure today and at idle had 32 PSI and removing the vacuum line from the regulator to simulate WOT got 40 PSI.

I was going to pull the rear tank and change the pump since it needs it anyway and run from it exclusively and see if it still did it and then replace the inline pump if it still did it but then started wondering if it could be related to the tranny not moving randomly. There does not seem to be a correlation to it stumbling after it didn't move though.

Anyone seen this issue before or have any suggestions before I start throwing money at it?

-GB

 

Two years later and I've started driving the truck daily again. Still stumbles but a lot more often (a few times a day). Yesterday I'm looking over stuff only to find the charcoal canister purge valve just hanging by the connector. I reach up under all the smog crap and feel an open connector where the valve is supposed to be connected. Started the truck ans put my finger on it and sure enough, there's enough pull to suck a golf ball through a garden hose. I capped it off and its like a have a new truck. I feel like an idiot because I've checked for leaks and it was so simple.

 

Way to go on finding the issue after so long, and it's great that you followed up with the post! and could potentially help someone else out down the road

 

That was my main reason for the reply. I hate looking for answers online only to find the same question asked with no answers. It's bad enough PhotoBucket has already screwed 90% of the online forums..

 

I'm having a similar issue. I'll check that out. Thanks