Driver's side: under the hood heat (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
May 10, 2020
Threads
23
Messages
122
Location
California
I'm noticing that the area around the brake master cylinder is quite hot after a few miles of driving, especially the upper part of the fender where it meets the hood. I have an under the hood insulator so I can't tell if that area would be hot too, or if it's more fender related.

I can't really tell if it's coming from the MC or from the metal A/C (?) line that runs along the fender. Note, the A/C is not even on when this occurs, and I have no brake fade or any other signs of overheating that I'm aware of. I do have kind of a random burning rubber smell too, but seems to be more passenger side focused. It may be unrelated, but just throwing it out there.

I guess in short, what could possibly be generating so much heat in this area?

Thank you.
 
I'm not going to burn myself, but it doesn't seem normal. I fist noticed because I felt the heat radiating from the area when I walked by, but I don't have way to measure it.

It's more like, why is this the only hot spot? Every other area, on both fenders, is cool. If anything, I would expect the passenger side to be much warmer.
 
Get an IR thermometer and shoot some temps to see if you can narrow it down. Seems odd.
 
It's a 96.

I'll get an IR thermometer and do some more detective work. Sounds like there is nothing obvious in this area I'm missing. I am certainly perplexed by it.
 
AC lines and MC should not be hot...however, the burning rubber smell is concerning...that points to mostly burning brake pads, is your caliper stuck? how is your brakes?
 
The brakes are great, stops like a boss and there is no pulling or drag. The hubs on the outside don't feel warm, but I can confirm once i get an IR thermo.

It's not a burning brake smell. I've found some threads on the mystery smell before, but no luck on what ever caused it.
 
Look for a blown out or disconnected EGR pipe. That is the only thing that would generate heat on that side of the engine.
 
Tuning in as I've also been recently puzzled about the same thing on a rebuilt 94
 
I'll get some measurements and be more methodical in tracking it, but in my mind it's got to be either 1) weird air flow, maybe due to the under hood dynamat pad, 2) brake lines getting hot and heating up the MC and/or ABS or 3) the AC line running along the fender, or 4) totally normal and I just never noticed.

There isn't anything else close to that area that could be producing that much heat (EGR is all refreshed and really not that close).
 
I'll get some measurements and be more methodical in tracking it, but in my mind it's got to be either 1) weird air flow, maybe due to the under hood dynamat pad, 2) brake lines getting hot and heating up the MC and/or ABS or 3) the AC line running along the fender, or 4) totally normal and I just never noticed.

There isn't anything else close to that area that could be producing that much heat (EGR is all refreshed and really not that close).
Brake lines do not produce or transmit that kind of heat.
 
I noticed after doing the PHH bypass loop on mine that the area above the BRake Booster (my PHH bypass loops around the Brake Booster was noticeably warmer. I only notice it on cool Fall or Winter days. You cannot feel it in the Summer.
 
I wonder if the passenger side would be just as warm, but it gets convection cooling from the air intake? Can anybody with a snorkel confirm if their fender is warm after a drive?
 

Users who are viewing this thread

Back
Top Bottom