Throttle hesitation and almost dies

[Classicfordguy]

Hey guys, my 94 F250, old faithful, just started acting up. Was hauling logs to the wood pile last night and noticed the engine running funny. If I try to rev the truck it requires the pedal to be depressed much further and it hesitates then when I let off the engine almost dies then levels out again. I have my suspicions that my injection pump may have bit the dust but would have expected that to be more gradual.

Bit of back story. Truck has been sitting for a number of months as I sold the lawn business and the camper. Last weekend I brought the truck and a trailer with a skid steer to the new house about 100 mile trip. It worked beautifully, the trailer load was prob 10,000 lbs. This week I've just been using it to haul logs to the log pile when the problem cropped up. I rebuilt the engine 5 years ago and have maybe put 15K miles on it since. New injectors and internals but same old injection pump with maybe 240K miles on it.

Any ideas?

Thanks!
-Rob

 

[franklin2]

Check the fuel filter. You may have grown some nasty stuff in the tank while it was sitting, and now doing off-road work may have stirred it up in the tank, and it's clogged the filter.

 

[redneckaggie]

I would change the fuel filter and fill it with atf, crank and let run through ip, kill it and let it sit over night

 

[Classicfordguy]

Sounds good. There's an international dealer close to the new house, I'll grab a new filter and give it a shot.

Thanks!

-Rob

 

[icanfixall]

All the above posts are what I wouls suggest but add just one more. Get a rebuilt pump from Mel & Conestoga Diesel. Yours has run twice the normal mileage so it has paid for itself twice over and its long overdue for a rebuild. Kinda happy to see you got twice the mileage out of it but its time. But first ry the filter and aft. That might give you more time but know its really past due.

 

[Classicfordguy]

Whoops! just read my initial post. Truck has 142,000 miles not 242,000 so that being said it very well may be time for a new IP. What's the average life of an IP and what are signs of a tired one?

Thanks!

-Rob

 

[bigoilburner20]

heat soak gets too hott and dies but starts up next morn something like that

 

[hallgren87idi]

125k is about the avg, but mine has 140k and is still going. just depends

 

[redneckaggie]

Most here say 100,000 miles but I have seen them die with only 50,000 and I have seen them last 250k I like to keep a spare around just in case but I wouldnt worry abut it unless it is definately dead.

 

[Classicfordguy]

So I did the new filter and filled it with ATF, let it soak overnight. Next day I began using the truck pull a stump. Took forever to start the first time but after that it got better then after a number of stops and starts the truck seems back to normal! Sweet! Thanks for the ideas.

So the fact that the new filter and ATF worked what do you guys think it was? If it were a clogged filter I think it would have fixed it right away so do ya think its dried out seals in the IP or something?

Thanks!

-Rob

 

[redneckaggie]

sticky valves and springs in the ip would be my diagnosis

 

[Classicfordguy]

That would make sense. Thanks for the help!

-Rob

 

[dgr]

Just to be clear, after you filled the filter with ATF you ran it until the engine got quiet and then shut it down and left it overnight?