Sputtering during load between 30-50mph
Where you getting a sluggish or sputtering from accelerating (load) on the engine while driving between 30-50 mph. My F-150 1999 4.6L has 169k miles and it was throwing the P0401 code and the P0133. The dealership suggested to change out the DPFE module and that cleared the SES light. But the sluggish sputtering is still there, with some (back fire like sounds when it gets over the sputtering). The EGR is the original, does that effect the fuel delivery while trying to go up hill at 30pmh?
There is no leaking of water/coolant on the spark plugs, they are all dry. The engine runs perfect at idle and general cruising. It just does this after letting up on the throttle and then pressing it down when in that passing speed of 30-50, very prominent on uphill acceleration (gas tank at full).
I will be chaning the fuel filter tonight to see if that changes anything. Then taking a look at the throttle body and vacuum testing the intake gaskets for leaks. It has a new air filter on it.
Any help would be appreciated.
Thanks in advanced.
1999 F-150 XLT Ext LB 4x2 4.6L 169k miles