I just bought a 1994 F350 7.5L with 50k miles. Does anyone have any idea why it sort of hesitates to start? Watch my video below to see what's going on. It doesn't roar to life like it should; instead it sort of just slowly rumbles up to speed. Sometimes it's worse and will actually die, and other times it will actually start like a normal vehicle, but that's not too often.

 

Your battery voltage looked a little low before you started cranking... do you have a multimeter? It seemed good once it was running, but maybe something is draining it when the truck is off?

 

Fuel pump!

Just went through this with my front tank on my 95 F150 with only 95K miles. It was starting "hard", stumble, etc. Ran it dry, installed new pump and presto it fires up instantly.

The old pump gets weak, won't always put full pressure to the fuel rail, thus it stumbles to run. Mine was random, but getting worse. Better to do it with an empty tank then having to empty it after you just filled it up.

 

Well, you have to ask yourself a question, do I feel lucky?
Do I throw parts at it or do I diagnose it?

You haven’t completed a complete tune-up yet….
You haven’t checked the Codes yet….

I would check the fuel pressure before I purchased any fuel system components.
750 Post; you know all this……

 

As was stated before, check for codes. Get a fuel psi reading, with engine off, key on. Then key on, engine running.

Check plugs, inspect cap and rotor.

Start with free, or almost free basics and diagnostics before throwing money and parts at something.

 

Problem solved. Turns out the ignition timing was waaay retarded. It was at like 0 deg BTDC, so I disconnected the SPOUT plug and set it to 12 deg BTDC. It starts with ease and is like a whole new engine now. I think the PO or someone must have tried setting it without disconnecting the SPOUT plug, thereby totally screwing it up...

Thanks for all the advice everyone.