burning/burnt smell at highway speed???

[jaymac]

I've had this issue for a long time now, but never cared enough to ask about it, but why not drop the question. On the hiway, my car will run 3 grand @ 75 mph.
Even @ 65 & 2750/2800, I will start to smell something like a burning.cooking smell. I believe I've always had it. The temps have always risen at highway speeds, from 180ish to 195*, but that's nothing new, and it doesn't smell like anti-freeze. Nothing's ever smoked or boiled over.
What do you think it could be? Oil? Need an oil cooler? Tranny fluid? I do have an aux. tranny cooler?
It doesn't necessarily seem to hurt performance, but I've never smelled anyone's car cooking on the highway before...
How bout the diff. fluid?? I can't remember if it did it before the 4.10's, but I think it did....

 

[Swarzkopf]

My first guess would be a leaking rear main seal, slowly spewing oil onto your hot exhaust pipes and burning.

 

[wht93gtEd]

it all depends on what kind of smell it is...for example;

- brakes have a certain smell
- anti-freeze has it's own
- oils have a certain smell
- plastics have smells

you need to determine what kind it is. is it speed or RPM that causes the smell? Say you drove around at 3k in 2nd gear....will you still get the burning smell? How long does it take for it to happen...can you rev the motor for a minute or 2 with the hood up to see smoke?

How bout the diff. fluid?? I can't remember if it did it before the 4.10's, but I think it did....

I don't think you could smell that at highway speed since the odor wouldn't be traveling forward at speed.

 

[wht93gtEd]

deleted

 

[jaymac]

well, nothing ever smokes, the rear main seal was replaced last year. It doesn't smell like antifreeze, and there's no excessive brake dust, and the pads were replaced last year, and the shoes usually make noise when they go bad. If anything, I'd have to guess a plastic smell. It does not do it if I drive at 2500-3000 around town (although I'll have to double check that theory to make sure). I start to smell it within 1-2 minutes of reaching 70-75 mph, as my only highway trips are 8 minutes tops. It's weird...
If I rev the enigine and look under the hood, I'd have to check again, but I don't think I'd see smoke; it never smokes on the highway... I'll have to drive it, pull off, park it, and sniff around....

 

[ninety1gt]

mine smells after dogging on it to, i think its the hts coating on the headers, cause i've never gotten that smell since the install

 

[jaymac]

I have the chrome BBK's so I don't think it's them....

 

[HISSIN50]

If you think it is tranny fluid (it smells plasticy to me), drive to it where it makes the smell and then pull over and pull the trans dipstick and see if the smell is the same.

Good luck Jeremy.

 

[8950HO]

I`ve noticed a weird kind of metallic burning type smell over the years too thats hard to really accurately describe when I`m flying on the highway at highspeed/revs with the windows closed.(theres no smoke in the car period,just that weird faint smell)

It`s a faint smell,but it`s definately there...totally weird and I`ve never been able to pinpoint the cause.
There`s no exhaust or oil/coolant leaks.

I`m at a loss on this one.Only happens when I`m really nailing it.

I wonder how many more others have experienced this?

 

[jaymac]

8950HO, that's what I got goin' on...faint smell, no overheating.
JT, What's up?! I'll try that... I should have a trans. temp gauge, too... how hard to install one??

 

[HISSIN50]

J - not hard at all to do the gauge. You can either use a manifold from AM to install it on the hard lines, install it in the pan, or cobble together brass to install it in a Tee in the rubber lines to your cooler.

It would take no longer than doing any other guage, other than any extra work you need to do (dropping the pan to install a bung, cutting the hard lines, etc). I think the best method is to put the sender on the output line from the trans to the cooler since that is the hottest fluid (the pan is a mix of hot and cold fluid).

When you get around to doing it, lemme know if you have questions.

Good luck man.

 

[jaymac]

1st question: cobble together brass?
Care to elaborate for your ignorant friend?

 

[8950HO]

Usually the term "cobble something together",means to slap or piece or mend something together roughly.

As for that weird smell,I`m still at a loss.

On the firewall on the foxbody there are holes covered with rubber insulating gaskets,like around the steering shaft,and the AC water drain hole is right by the header flange on the passenger side.

Maybe on hard high speed acceleration the exhaust heats up more and emits this smell that somehow gets inside the car.

I am not hallucinating at all.
Theres been countless times when I smell this weird smell after nailing it,and I`m like,sniff,sniff,inside the car saying to myself,wtf is that.And it doesn`t smell like exhaust gas either.

 

[HISSIN50]

Cobble is the act of making cobbler.

Seriously, you got it - piece together a brass tee and adapters (like we do for oil pressure guages) to fit the gauge sender and the line that was cut for the tee. Just like with the oil pressure Tee fittings, there are several ways to do it.

 

[jaymac]

cool enough; I found some gauges and pods pretty cheap...

 

[jaymac]

8950ho, do you have an AOD/torque converter?

 

[Michael Yount]

jaymac - if the cooling system were doing it's job properly, the temp should NOT rise to 195F when you're cruising down the highway if it's maintaining 180F at lower speeds. Despite the revs, the engine is actually barely working (in terms of HP development) at a 70-75 mph cruise. Any vehicle should sit right at the t'stat temp during a highway cruise at moderate speed. So for the temps to climb probably indicates you've either got a radiator issue or an airflow-across-the-rad issue. Once you get your 'smells' figured out, I'd look into it.

 

[jaymac]

Well, the cooling system is definitely not doing its' nob properly anyway. It's leaking through the block/timing cover surface due to a broken bolt. The heater core must also still be gunked up/clogged, as my heat still doesn't work. Beyong that, the rad. is one I put in a few months ago that I had in storage for awhile, but had only been used for a few months (a few years ago). It "shouldn't be a problem, but of course, could be
Which (if not all) of the above probelms do you think could be causing the "rising at highway temps" problem, and also, do you think it could be related to the fact that my system does not suck overflow back into the radiator????

 

[Michael Yount]

From previous post --- "So for the temps to climb probably indicates you've either got a radiator issue or an airflow-across-the-rad issue."

If you dont' have the black plastic spoiler at the bottom front of the car, put it back on. If you do, then I suspect radiator/inside of the engine or both is full of deposits. Once you get it clean (if that's the problem) running antifreeze and ONLY DISTILLED water will eliminate most new deposits from reforming.

 

[jaymac]

I do have the black plastic piece.
What's the best product in your opinion to clean deposits?