2000 F150 4.2L V6 Auto - Motor runs great but for several years now, it has an infrequent miss in overdrive under load like climbing a hill. May miss once or several times in a row with break in between. Sometimes, no miss at all but missing is on the increase.

Changed plugs, wires, & coil pack. Taken to several mechanics. Mechanic sees no codes. Head gaskets changed with no effect. Questioned transmission torque converter shudder but does not shutter, more like a single plug firing miss.

Runs great on idle and every gear but overdrive.

Anyone had a similar experience? Any suggestions on what to look at next?

Thanks for any help!

 

check the injectors. or could be the torque convertor slipping how many miles on it?

 

I had exact same situation a few years back in a 302 van with e40d overdrive trans. It drove the ford techs nuts for a while but finally the service manger figured it out . Long story short It was 2 bad wires that were replaced and the problem never returned. I don't know that this is your problem but I thought I'd post it anyway.

 

Thanks for the feedback. Because it is intermittent and a single, independent missing, not a shutter, I just couldn't help but think that it was electrical in nature. But, I was struggling with changing all the electrical components and sensors without some kind of direction and non of the mechanics were giving me any hope. Sounds like you've been through the same situation with mechanics looking at you like you have two heads. Will check transmission model and start checking wires.

You wouldn't happen to remember which wires were bad or did they replace all of them?

Thanks for the help!

 

Just thought of something. Are you saying that they replaced the plug wires or electrical wiring to transmission?