Melted wire harnesses on v6 coils

Ok. I will replace that first then check back. I'm pretty sure its not gooped from the factory unless the last tune up I did at the dealership they gooped it to hold it together. The wire was so difficult to detach since the rubber had melted to the top of the coil where it plsgs in at that I used a knife to cut them apart. Luckily I didn't cut the wires below. The other 5 wires detached easily.

 

So you've confirmed that the actual connector is melted and what we are seeing isn't just black silicone?

 

Yes it is melted. When the sun comes out i will take it apart and taje a picture of the inside of the plug.

 

that is goop someone added it must be

connectors don't melt like that unless they burn as well
and you'd see much more damage

 

So would to much goop cause the wires to not perform correctly and make the truck misfire? Only time the connector has been touched was when the dealership changed it the plugs 50k mi ago. Unless someone spilt goop on it at the last oil change but that was almost 2kmi ago at the dealership.

 

Source, terminals, seals, and plug - $6+3 shipping
http://www.bmotorsports.com/shop/product_info.php/cPath/0_109_182/products_id/1667

 

See if you can clean the rtv or whatever it is off the connector and take another picture. Maybe the plug is fouled with goop maybe the coil is bad. If it turns out the plug isn't really melted then you want to swap coils and see if the misfire moves.

 

I wonder that too. Seems like overheated wiring would start from the inside where the wires and contacts are and you would probably have some internal damage or melted wire insulation as well in that case. Seems possible some type of added goop might possibly affect the connection if it got under there or allowed moisture in or something like that.

I reckon I've been watching too many Forensic Files episodes lately...

 

I just took it apart. The pics above are off the coil and wire harness. There is no damage at all on the inside of the wires so that material on the outside of the wire must just be goop or extra silicone from the factory. I took out the spark plug, checked the gap which is at .41 and replaced it back in the block. I reset my ecu with my obd2 scanner. About to drve it around today to see if it comes back on. Since its not the wires melting im pretty sure its the coil thats gone bad and I will replace just that one and try again.

 

Thats definitely some kind of goop, sealant,silicone. You can see the glue stings on the coil. Just use the link I posted or the P/N that Caribe posted and replace the connector. $6+$3 shipping at my link. I just bought 6

 

ya i was gonna say even from the first pics, that thing isnt melted its just got black silicone on it.

 

I was right...

 

Ok dumb question. Is cylinder #4 located on the drivers side closest to the front of the vehicle:
Back
3 6
2 5
1 4
Front
Or is it the drivers side cylinder in the niddle like this:
Back
5 6
3 4
1 2
Front
I replaced the coil on the driver side closest to the radiator and its still doing the same thing. Im thinking I replaced the coil to #2 cylinder thinking it was #4 cylinder

 

I replaced the coil on #2 and not #4. I switched them out. About to reset the computer and test drive it. Im guessing the old 3.4 is different because the diagram I googled was different then the one you just posted it. Thanks for your help.

 

Well I test drove it and the p0304 code came back up on my scanner. The truck drives fine but whenever I start the truck from cold it idles and stumbles real hard for 30-45 seconds then it settles down. It only hesitates when I first start it but drives perfectly fine. If I shut it off and turn it right back on it doesn't hesitate. If Ishut it off for a few minutes then turn it back off it hesitates for 30-45 seconds again. Anything else I could look at besides the coil and plugs on cylinder #4?

 

Yup - compression test, check for any coolant in cyl #4. Before compression testing, crank the engine with plug #4 removed, while a helper holds a white paper towel near the spark plug tube. Dampness or pink coloring on the towel is a bad sign.

If OK on those two, swap the #4 injector with another to see if the issue follows.

 

My simple mind boils an engine's operation down to three simple needs... Air, fuel, and spark. Air is probably not the problem, so spark or fuel. Scan says #4, so since you've checked the wires (assuming) I'm wondering about a clogged/dying injector (some argue a clogged injector won't cause a cel, but thought I'd bring it up) best to you!

 

Im going to take it to my mechanic friend tomorrow. I could only imagine how much the dealership is going to charge. Im going to be pissed if its the head gasket because i flush the radiator every 50k at Toyota and run 5w30 royal purple oil with oil changes done every 5k mi since the truck had 65k on it.