Hot exhaust burning rear carpet (3 Viewers)

[Andrew Bluemel]

I’ve never noticed my exhaust being abnormally hot. That is until I was going through the mountains and I smell burning from the back. Come to find out that underneath my passenger second row seat the carpet was burning and the whole floor was stupid hot to the touch. The rear heat shield underneath the second row where the exhaust runs is still intact and coolant temps never get over 195 on the hardest climbs.

My Cats were replaced 8 months ago
I thought maybe a crack in my Y pipe would be upsetting the fuel air ratio and the 02 sensors so I welded up my Y pipe and replaced the 02 sensors. No change

Any thoughts on what else this could be caused by?
Thanks

 

[leonard_nemoy]

Sketchy, that is weird. Maybe the new cats are getting to hot. Did you replace them with OEM?

 

[Andrew Bluemel]

Sketchy, that is weird. Maybe the new cats are getting to hot. Did you replace them with OEM?

No they were some generic cats that a local exhaust shop said would work. I’m going to go to the store and pick up a infra red temperature reader and I’ll post up the temps on here from the Y pipe, Cats, and where it’s burning through.

 

[leonard_nemoy]

Sounds like a good idea. I wonder if the cats are creating to much heat. Is the rest of the exhaust in the original location or has it been replaced or moved closer to the body?

 

[Andrew Bluemel]

The exhaust has had bits and pieces done which I regret. Wish I just did it all at once. Original Y pipe, New Cats, and a new muffler and resonator at a different time.

Here are the numbers I’m pulling from a 10 minute drive. Does anyone have numbers to see if mine is within spec at the various locations? It’s confusing to me in my limited knowledge why the spot under the rear seat would be warmer then the muffler.

And in the interior the temperature just slowly kept tip toeing up. I’m thinking I need to have someone move the exhaust lower to promote airflow between the exhaust and the bottom of the body but I want to make sure these temps in other places makes sense and the motor isn’t pumping out drastically higher numbers then everyone else.

 

[Andrew Bluemel]

 

[cvenom96]

Did you ever find a solution to this? Same thing is happening on mine. I was getting stuff out of the back through the side door and the floor latch for the seats almost burned me had I touched it longer. I haven't noticed this before but what I think might be happening is since the truck has 37s now and hasn't been regeared, it's just heating up the exhaust more with trying to move itself. It's basically right over where the exhaust peaks above the axle nearest the floor.

 

[TYM4FUN]

I have run into this as well. Exhaust is just really close to the floor there. My kid burned their foot on the second row anchor.

Please read. * Caution...Daughter burned her foot on 2nd row seat anchor.

I have never noticed how hot this anchor gets. Looking now, I realize how close to the exhaust pipe it is. She was wearing flip-flops and took them off. As she was exiting from the 3rd row, she stepped on this seat anchor and burned her foot. So please be aware if you do not already know. I...

forum.ih8mud.com

 

[mudgudgeon]

I remember sitting in the back of my parents car when we were towing a van on holidays and burning my feet on the seat anxhor bolts for the front seat.
It got hot enough you could not touch the seat bolts for even a second.

 

[mudgudgeon]

What about some additional heat shielding.
Something like this that is mouldable, and cut-able

https://www.tiperformance.com.au/wp-content/uploads/2018/08/2018-Permaseal-GTB801-Heat-Shield.pdf

Kool Wrap 6 Layer Exhaust Heat Shield 68cm x 43cm

Kool Wrap Exhaust Heat Shield sheet 68cm x 43cm. This corrugated heat shield is made from a 6 layer aluminium design, making it super easy to form into shape. When formed over exhaust manifolds, turbos, and dump pipes these shields provide a factory like appearance and unbeatable engine bay heat...

www.tiperformance.com.au

 

[2000cruiser]

Could it be mounted too close to the floor? Perhaps some space would help?

 

[TYM4FUN]

Could it be mounted too close to the floor? Perhaps some space would help?

That is where it goes over the frame to give clearance for the rear axle and suspension...

Toyota already clearanced it, by squishing it into an oval.

 

[2000cruiser]

That is where it goes over the frame to give clearance for the rear axle and suspension...

Toyota already clearanced it, by squishing it into an oval.

Other than the heat shield, maybe lava wrap will work?

Lava® Exhaust Wrap

The original basalt rock wrap - Lava™ Wrap

www.heatshieldproducts.com

 

[NorCal97]

An overly hot exhaust is likely a symptom of an upstream problem. Assuming heat shields are good and the exhaust hasn't shifted closer to the body for some reason, I'd be taking a serious look at everything that could a rich air/fuel condition. The cats will faithfully burn excess combustibles, as intended, and will get stupid hot if overloaded - as in, the guts can melt. Mine did this some years back when the primary O2 sensor went kaput.

 

[Andrew Bluemel]

Little late to the update here but I ended up taking it to a exhaust shop and they spaced the exhaust down a bit so it didn’t melt the carpet. Bandaid on the solution. Then fast forward to last December and we slapped on a supercharger and noticed it was pulling hard then falling off a cliff after 3k. My hypothesis was the Cats being clogged and eventually one day there was so much back pressure really romping on it one day that it blew a vacuum line off the side of the block. So we cut out the cats and now it rips and no more weird back pressure issues. And the motor runs way cooler I never see over like 195 anymore. Although my cats were only 50k old my hypothesis is I got bad or defective cats and it was my problem all along. Take it for what it’s worth but it’s crazy how much happier it drives without the cats. Plan on putting on a single high flow eventually but not rushing to do it.