Fear

I have a 2009 4.0 and i have recently started smelling something thats just off..

It was a weird smell like burning rubber but not quite. ( i thought maybe it is rubber but i smell it on startup while i let my car warmup before i drive)...

I checked all fluids, had oil changed less than 1k miles ago (i checked oil and its still on full line)... Any ideas?

stupidgenius36

I experienced this same thing a couple summers ago. I'd get out of my car and all I could smell was rubber burning.

It smelled like it was somewhere in the engine bay, but I was never able to find exactly what it was. It went away by itself, and hasn't come back.

austinkli

Did you check the serpentine belt to make sure it's not starting to stretch and melt a little?

If you keep your engine bay clean it should be pretty easy to find any oil leaks you may have. Though burning oil has a fairly distinct smell. If it smells like it could be burning rubber, it probably is.

The only other thing I can think of could be an exhaust leak, I'm basing that idea purely off the fact that it's winter so when you start your car it's probably a cold start. I'm not sure about mustangs, but a lot of cars will run slightly rich until it warms up, then it'll run normal. Though that smell would be more like the smell from your tail pipe.

Fear

hmmm ok i didnt think about checking the belt! ill check on that when im home... As far as the running rich on a cold start, i can smell it for an entire drive (it just starts at beginning but continues through the drive)

ford4v429

look close at your harmonic balancer too- eyeball across the pulley faces, make sure they are inline, as the 4.0 has had a tendency to throw the lower pulley, causing the belt to eventually ride off and run on the hub of the balancer...theres a thread in here somewhere on it, several guys mentioned it...pics showed the lower pulley rim way out on the edge of the balancer(ready to fly off) and the belt riding behind it... that and thermostat housings are about the only problems ive heard of on the 4.0

Fear

hmm ok ill check on that. and yeah ive already had the thermostat housing happen and it doesnt seem to be the same.. when it was that my engine temp skyrocketed and it dumped all my coolant.

GottaHaveIt

check the positive cable my disintigrated once and melted on the manifold , or if you have any secondary power wires on the passenger side as the smell would come in throuh the cabin filter.

Fear

positive cable of the...? Battery?
And my left hand side headlight has seemed to burn out a few days after the smell started up.. hmmmmmm ... will have to take a good look this weekend

907stang

I have a 2005 ford mustang 4.0 v6 with a manual transmission. The vehicle has 57,000 miles and I have never had any issues with the car since I bought it
until recently while driving down the highway in cruise control i started to smell a odd smell then started to see smoke coming from the vents so I pulled over shut the car off turned it back on and now it will not move what's so ever I can put it in any gear release the clutch and nothing. I have perfect clutch pressure I checked the fluids I am not sure where to even begin.

05stangkc

@907stang

Welcome!

Sounds Like The Clutch Just Let Go. Sometimes They Start Slipping Before Going and Other Times Just Let Go!

Here Are Some Shop Manual PDF'S on Trans & Clutch Section.

Anyhoo, Thats My Guess With Info Provided. Might Get Er up on Jackstands Get Close To Bell Housing and See if You Smell Some Burnt Clutch

Feel Free To Start New Topic Next Time You Have a Concern! We Got Plenty o Space!

KC