My truck has been running really rough. It idles rough and when you go to take off from a stop it sputters in first through 3rd gear during excelleration.

Seems to run fine at speeds above 40mph.

I changed the spark plugs, wires and distributor cap. Still having the same problem...

Ran fuel injector cleaner through it, no change.

Checked for intake leaks, there are none. I do have a small exhaust leak on the exhaust manifold.

What do you guys think?? Should I have the fuel injectors checked out?? Something else I should be looking for??

 

Fuel filters are cheap and e-z to replace. My 85 300I6 has a carb so I am not sure of how many and the locations of the filters to replace on the EFI motors. Check the motor spark plug wires at night for sparks were they should not be. Whats the air filter look like?

 

Air filter was recently changed. Would a bad EGR cause problems like this?

 

Don't know about EGR valves but I do know about dirty fuel filters. How new are your FUEL FILTERS. Another thing to check is the fuel filler cap. Some times they get pluged. Try removing the cap for a short distance.

 

How did you check for vacuum leaks? These are bad about sucking the throttle body gasket in and causing strange driveability problems. The only easy way to detect it is with a smoke machine. Look down the TB with it held open and see if the gasket is sucked in.