Percolation? Heat soak? Don't drive during summer??

Try not to use electrical tape to wrap the harness. There's a wrap tape which has no adhesive that makes far less mess when you remove it, or when it gets heated. You pull it tight and it also shrinks slightly with exposure to heat. Works great! The ends are typically affixed with adhesive tape though to prevent unraveling. I like to use the fabric stuff though, looks like hockey tape. It holds better to itself and doesn't become gooey or slimy over time.

I used black hockey tape to re-wrap an entire wiring harness for a 1991 vw gti that I had a long time ago. That stuff works good.

I was just trying to clean up some of the wires from the ecm. They were all just flopping around.

I have some plastic tubing stuff to stuff the wiring harness in and clean up the entire engine bay. I just need to get the small circumference one as well for where there aren't as many wires.