I have a 1994 Ford F-150 4.9L with 105,000 miles. When I hit the gas to get moving, it will stumble to 500-600 RPM and then spin back up to 1100 RPM where I originally wanted it. If I let it warm up for a while it still does it but not as bad. I put new plugs and wires on less than 2000 miles ago so I don't think it's that.

Any help would be greatly appreciated

Garrett

 

Does it always do it or only sometimes?
Did you replace the the cap and rotor? Usually has to do with the cap and moisture, very common symptom.
If that's not the problem, check for stored codes, if no codes, pick up a manual, start the diagnostic and troubleshooting process.
It could be damn near anything causing this symptom.
If you have dual tanks, does it do it on both tanks?

 

Thanks for the starting points, I didn't replace the cap and rotor. It isn't throwing any codes at the moment. I'll check and see if it is doing it on both tanks.

Thanks

 

While not a "proper fix", some of us who have had an issue like this have "fixed" it by limiting EGR flow. Placing a tightly crumpled up ball of aluminum foil in the EGR valve (too large to ever escape), was recommended by a Ford tech. Obviously this was not a Ford-authorized tech bulletin.

Feel free to search for further details or other solutions relating to EGR flow.

 

Beat me to it. First thing that came to my mind, although I'd recommend fixing the EGR system just for the improved gas mileage.

Also check all your vacuum hoses. Very common issue and easy to fix. Those nylon lines are prone to cracking too.

Maybe dump a full can of Sea Foam in the gas tank (yeah, I don't usually recommend additives, but do for this condition).

 

There was a ford tsb on the throttle body gasket leaking. Mine was at 150k miles. In addition I put a restrictor plate in the egr with about a 3/16 hole. Much improved stumble. I still have a slight stumble on tip in but I wonder if my expectations are too high of my old truck sometimes.

 

That's a good one too. TB gasket is a two dollar part and takes 5 minutes to install. Was harder to find than I expected. Ended up searching online for a local store.