Avalanche vs Drain curb

[SHOW_STOPPA]

Hey everybody... I noticed a thick black "sheet" about as thick as cardboard ...sneaking out of the engine bay into the door hinge on the driver side of my beloved avalanche. I am wondering if that is the firewall and if so...how/why could it be doing that? A while back I hit a heckuva storm drain curb that bent my rear axle and ruined my 7000$ wheels. 2 weeks after i bought them. The drain was on the passenger side. So I'm wondering if that could have caddywhompused my engine bad enough to cause water/coolant to get in the motor (because it is smoking real bad and the number 7 spark plug is smashed ..theres no gap...as well as oil on the plug) but I had just bought my truck 30 days before hitting the drain. I was raised by a single father with his own very successful mechanic shop, so I tried to do a thorough inspection before paying $11000 cash for my 07 that needed tires and headlight n rear view mirror n windshield etc....I have cried more over this show stoppa than I care to divulge but I need some help.
Thanks in advanced.

 

[Wpolonavyguy]

Yes it's probably firewall or noise dampening matte. Idk how it got loose or moved but sounds like that's what you see.
Unfortunately sounds like expensive engine problem, have mechanic look asap. Unless you plan to diy. But smash plug sounds like something very catastrophic could have happened or about to get worse.
Good luck