Hello I have a 1989 f250. It has a 302 small block, 5 speed manual, and 4x4. I bought it about three months ago and it has developed an issue where it surges under load after 2700 rpm. The truck is just about completely stock with only 76000 miles. I have replaced the fuel filter and pump and did a tune up. The truck also is very low on power to the point where I have to downshift two or more gears to make it up most hills. Those two issues migh be related but I am not too familiar with the fuel injection system used on the truck and need some help. I know that the 302 is not a real stump puller but I would think it was more powerful from the factory. The truck sat for long periods of time as it was only used as a hunting truck a few times per year before I purchased it.

 

Have you checked the ignition timing? It could have "jumped time" or the distributor mechanical or vacuum advance unit could be bound up, not letting the timing advance as it should.

 

Check the entire intake system for vacuum leaks. Serving suggestion

 

I'll take a look into it thanks.

 

I would check for a stuck EGR Valve. You should see it move by applying a vacuum source to the valve, even without the engine running, or unbolt it and see if the plunger is stuck or the valve needs cleaned.