I had a potential buyer test driving my truck. 2006 F150 4.6L XLT 4x4. They said they engaged the 4WD and shortly after the truck nearly died… they had the A/C on max, fans on max, just testing things if they worked.

I have white smoke and liquid gasoline dripping out of the tailpipe. Dash light was on with codes P201 P204 P206 P207 P208 P443 P748 P962 P2198. All these codes mention “A” circuit. I suspect either a fuse is blown somewhere or something else electrically in common. I did find 1 blown fuse #41 for the OBD reader port. At this point I’m slowly going through all the fuses to see if any others are blown. Any advice? Am I on the right track?

 

Ignore the "A circuit" bit, that's probably just generic language that your scan tool manufacturer or software developer put in there.

Are you sure you don't have more fault codes? If you lost power to all of those circuits, it's probable that you should have somewhere north of a dozen codes posted including all 8 cylinder injectors and every sensor/actuator fed from the same circuit supply.

 

That is all. I did get it started today and drove it around without any issues… reset all the codes, waiting for anything to come back. Someone mentioned to me about the EVAP pressure in the gas tank, since the truck has been sitting the EVAP valve vent may be stuck and not pulling gas through? Didn’t make sense to me because of the running rich but I tried his “undo the gas cap”. But driving it while tightened did not bring back the issue.

 

The fuel cap deal would have nothing to do with electrical circuit faults.

Sounds more like a connection or component going intermittent.

 

I am thinking it’s electrical but I don’t actually know. It’s possible it isn’t. I have not found anything concrete that may cause the issue and I haven’t come across anything remote to this issue before. Bad luck it happens as soon as someone test drives it!