redfishtd

Been fighting this l long time . Noticed right hand wire loom on computer plastic sheath had failed due to plastic breaking down with heat . This caused weight of wire loom to pull down hard on this plug pins . I pulled it up and duct taped it good . This plastic wire covering is crap in the heat . Poor engineering-- cheap cheap .
So far no miss , If it holds up I will fix it better and look at beefing up other wire looms with heat resistant stuff. This plastic just falls apart in your fingers.

redfishtd

The computer is in the hot engine compartment on the passenger side and the plug is the one on the engine side . The wire loom is very tight no drip loop or strain resistant provision ,it is just taped to the connector so I redid this with duct tape .
I have no idea what signals are in that plug , maybe the cop ignition signal or the fuel injector signals ? If you know let me know , I don't have any diagrams . I was about to start changing fuel injector plugs and cop plugs .

MGD

Pull any stored/pending codes, misfire data, etc.

If you've been missing for a 'long time', you also may have been dumping raw fuel into the cats just as long. Which will kill them.

After 9+ years, my old truck never had any underhood plastic failures of any sort.

BTW - 2005 5.4 3V? You should really read this: http://ww2.justanswer.com/uploads/sd...229_r07m08.pdf

jb2012

I have a 4.6 which may be different, but I replaced the main engine wiring harness, which plugs into all 8 injectors and coils. This harness plugs into the pcm on the passenger side of the computer.