Relearn nightmares...

[csc]

Picked up my son a 07 explorer xlt, 4.0 V6, to beat around in. It has 140,000 miles so I figured I would give it a tune up. New plugs, old ones were original. Also cleaned the throttle body. Truck ran, fine besides a small fluctuation in the idle, for 2 days. My son got home and mentioned the idle was high at times, so I decided to do a relearn. I disconnected the battery, cleared the pcm and tried to fire it back up. It was idling rough and in limp mode. After a few more tries of a relearn I was stuck with the same rough idle and no peddle action when running.

After some discussion with a friend I decided to replace the throttle motor and throttle position sensor. While replacing the sensor I noticed the wires that connected to the TPS were frayed and bare. I fixed them with electric tape and finished the install. After a relearn I was left with the same results, a very crappy running vehicle.

Upon further inspection I learned the wires to almost every connection under the hood was frayed and bare. The coil, egr valve,temp gauge, fan clutch, alternator and many more were bare right by the connector. I repaired as many as I was able to find with tape and a prayer.

Unfortunately the truck is still in "limp mode" for lack of a better term. When the key is turned on the throttle butterfly budges about a 1/8" 3 times then stops. If I press the accelerator the butterfly opens at the same time without a hiccup. It refuses to relearn and I am out of ideas.

Is my PCM fried? Anyone ever seen this before? Any help is greatly appreciated.

 

[Gorb]

Any pending codes when you put a scanner on it?

 

[csc]

Any pending codes when you put a scanner on it?

P2112 P2140

 

[Havfun]

Have you tested or replaced the accelerator peddle position sensor? Check wires at that sensor also?

 

[Littleant]

I believe when you disconnect the battery you are supposed to connect the pos and neg cables together with a jumper wire NOT THE BATTERY TERMINALS. This will discharge any capacitors in the system. Leave together for 15 minutes.

 

[Mbrooks420]

I believe when you disconnect the battery you are supposed to connect the pos and neg cables together with a jumper wire NOT THE BATTERY TERMINALS. This will discharge any capacitors in the system. Leave together for 15 minutes.

Shorted capacitors should discharge immediately. Disconnecting either terminal for 15 minutes should drain them as well. Capacitors store and release energy very quickly, they aren’t like batteries.

Seems extremely odd to have so
Many messed up connections. If the wires are bare electrical tape is only a temporary solution to electrical gremlins.

 

[Havfun]

Rats are known to chew and fray wires but the cases I've seen have been localized to one or two connectors under the hood.