It could be two problems you are dealing with it is very common for ford models from these years. but until now you are looking at the throttle body for issues or vac leaks, most of the time if you get dtc codes which behave very erratically specially if they are related to TPS or Trottle body are caused by worn off or damaged main wiring harness. symptoms are sudden loss of accelerator input, your car will idle or idle ruff due to fail safe mode but wont move and orange wrench light will come up, sometimes when the wires are not always shorting out this problem may come and go, Turning off ignition and turning on back again will very much solve the problem for few minutes until short happens again. This harness can easily get damaged just above the transmission due to poor workmanship from earlier repair or, if the harness mounting clip came off/broken it will strike the body and gets chewed up, if someone lifted the vehicle by jacking up the transmission or if you floored the vehicle in sand. for the throttle body adjustment screw i recommend to get it replaced as its very difficult to re-adjust the right amount of spring tension without the proper tool and if you already have high mileage on it is best to get replaced because even if you fixed it sooner or later it will be the next candidate to make you hire a cab back home>

 

Its been a few years but....
I did replace the throttle body assembly and been good since.
Now I know not to mess with stuff that I am not sure about until figuring it all out.
Appreciate the advice and reply.

 

Tps ( dirty throttle body, bad motor acuator) will cause limp mode, no peddle response, reving. Due to errcatic and dangerous peddle responses, stalling the limp mode comes on. If you spray throttle body cleaner in the throttle body you must change oil immediately because cleaner, Including the nasty stuff dilutes oil to much. To sufficiently clean the throttle body remove it, use only throttle body cleaner. Dont scrape surface your cleaning as it will affect performance. Avoid spraying wire, and wire socket.
. Low transmissiion fluid will also cause 08 Ford Explorer ,4.0 Automatic to go into limp mode to prevent tranny damage. Must be checked on level ground and at opersting temperature Correct level then restart ( a job within itself as it has no dipstick)should fix. Make sure you use only correct tranny fluid and no additives.Its critical. CHeck out Makuloco on google. Speaking from personal experience. Excellect Ford Guy. If its Ford hes your man.

 

Appreciate all that.
My issue was that I messed with a stop screw and wrecked my throttle body.
Replaced it a few years ago and has been fine.
Thanks