I've been hanging out on the transmission page because I thought it or the torque converter was going out due to slight surging at around 40 mph. Wondering if it was a misfire, I changed the plugs (Motorcraft Platinum) and COP's (from Global). Someone suggested that the DPFE maybe be the problem so I pulled the hoses and noticed the small part was completely clogged with white corrossion (I think). Well, I probed without going to deep and stuck it back together and the truck and the truck ran worse than ever even at an idle. I picked up a replacement DPFE and it still runs the same. I've tried the suck test on the EGR valve and it dies like it should. I also cleaned the thottle body before this.

Any ideas???? I'm ready to bang my head against the wall. Could it be the EGR solenoid? It seems strange that it ran worse after cleaning the port on the DPFE. It actually idles better without the hoses connected.

I appreciate any suggestions??

 

Sounds like you didn't disconnect the battery and reboot.

trans , convereter - The MAF sensor plays a Major part in operation. That may be dirty.

The DPFE won't effect the way she runs.

 

I disconnected the battery for about 15 minutes, is that long enough. I also cleaned the MAF yesterday after it start idling rough. Could a vacuum leak cause this? I could not find a new EGR gasket without ordering one so I used the old one. It didn't look too bad. I have some 3/8" vacuum hose elbows that look rough but I can't seem to find any of them either.

 

Does the MIL work?

Have you ruled out all possible fuel issues? Pressure and Regulator check?

Make sure your wiring harness isn't resting on the AC accumulator. This can effect your ignition system. If your engine is running rough @ idle , try pulling the harness further away from the accumulator. If idle fluctuates , your getting interference and need to reposition the harness.

Check the PCV valve and line all the way back to where it plugs into the manifold.

 

I fixed it. After changing the DPFE, one of the (8) COP's that I replaced last week went bad at the same time so that caused quite a headache. You don't expect something like that.

Runs good now.

Thanks everyone.