1995 T-100. Melted Spark Plug Connector! Please Help.

[T-200thousand-plus]

So my truck is a 1995 T-100 with 200k.
Started running really rough. Oil level was fine.
Turns out, it's not running on one of the cylinders because a spark plug connector was melted!

Here are attached pictures. Can someone tell me what parts I will need to fix this?
Looks like the underside of the plastic connector that hold the spark plug boot just melted.
Engine is still hot..so I haven't checked the hole in the engine, but I ASSUME theres still a spark plug in there... lol

Advice? Tips? What parts specifically will this require? Thanks in advance!!

 

[T-200thousand-plus]

To update this... I found out that plastic connector box is called an "ignition coil".
I purchased 3 on amazon for $50 total including next day delivery.
Will be replacing all 3 coils tomorrow hopefully. Also, spark plugs.
Since I'm only working on the passenger side, I might just replace those 3 spark plugs. LOL. (cylinders 1,3,5)

 

[tbplus10]

Its rare that those parts melt down like that.
Age is certainly one issue, also be aware of moisture shorting them out.

 

[rickc5]

That doesn't look like it melted--more like it died of old age. If you intend to keep the truck, I would definitely replace the other three too.

We all like Toyotas 'cuz they're so dependable, but after 23 years and 200k+ miles, it seems some necessary maintenance may be required on your truck. Just sayin'.

 

[seahog]

The coil could be not melted - but burned from a bad/high resistance/loose/corroded connection. Inspect the other 5 coil assemblies. If by visual inspection they are okay, leave them in. I would do a resistance check of the low and high voltage circuits of each coil. If the resistance readings are about the same, they should be okay. Would be nice to know what the entire plug looked like on the bad coil. BTW, was the coil damage/burning on the high or low voltage side? This happened 11 months ago, so you've solved this a long time ago, but your final repair info would be interesting to know, sir.

 

[kennythewelder]

The coil could be not melted - but burned from a bad/high resistance/loose/corroded connection. Inspect the other 5 coil assemblies. If by visual inspection they are okay, leave them in. I would do a resistance check of the low and high voltage circuits of each coil. If the resistance readings are about the same, they should be okay. Would be nice to know what the entire plug looked like on the bad coil. BTW, was the coil damage/burning on the high or low voltage side? This happened 11 months ago, so you've solved this a long time ago, but your final repair info would be interesting to know, sir.

You have a good reply, with good info, but IDK if you realize that this thread is 1 year old. Look at the bottom left of the thread, and you will see the date the thread was posted. Welcome to the forum.