Smoking smell under hood at 90mph+????? help!

[abcxyz]

Hi~

I own a 1998 328is, with about 114000 miles on it. Car still runs great, but have come across a problem in the past month that I'm unsure of. About a month ago, I drove to the airport from my house (about 30 miles) on the freeway going around 80 or 85mph to pick up a friend. Then I dropped him off at the place where he was staying (which was another 30 miles from the airport on the freeway). I didn't do any driving that was out of the ordinary, maybe went 95mph to overtake someone once, but again just driving around 80 or 85mph. Well when I stopped and turned off my car, a slight burning smell was coming through the vents of the car, and I opened my hood and it was smoking, but only for maybe 15 seconds or so. I have no clue WHAT was smoking or what the smell was. Well, I stayed at my friend's house for about an hour and drove home later on (another 40 miles) and the car was fine when I got home. I've driven it for a month now since then both on the freeway and the city (mostly city though) and it was fine. Then this past weekend, I had 2 other people with me in the car, and was driving to a restaurant, and at one point I shifted into 4th at about 80mph to overtake someone, and i had the car up around 95 to 100mph for about 5 to 10 seconds, then slowed down to about 80 again. Well I smelt that smokey smell again. Anyone have any idea what it COULD be? It seems when I take the car over 90mph or something it happens? I don't want to go on a long road trip and get stranded or something because something under the hood burns out and dies...

Thanks for anyone's help and/or suggestions!

 

[bmw046series]

Maybe you aren't going fast enough, if you got over 100 maybe the smoke would go away.

 

[chief]

Find any fur (tree rat) otherwise known as squirrel under the hood. Or perhaps a snake or cat got in there. If you can't see anything you may have cooked it into ash.

 

[Kirby]

Higher speed = more heat.

Check for debris (ie. plastic bags!) on the cat convertor or down pipe. This can stink for MONTHS after the initial "contact" (ask me how I know, hehe).

Also check for an oil leak that is pushing out oil at higher speed (higher engine pressures) onto the exhaust manifold.

 

[DSK]

Also check to make sure you don't have any wires/sensor cables etc in direct contact with the engine/thermostat etc.

I changed the crankshaft sensor only to have it constantly touching the thermostat and engine block, causing smoke etc, only to have to replace and get a special clip thing that holds its in place just so that it doesn't touch either of the two parts i mentioned.

 

[abcxyz]

Ok, thanks for your replies (well not the first two, those were rather ignorant/infantile), I'm pretty sure the smoke was coming from directly under the hood, closer to the passenger side...when i did open the hood, i was looking around when the smoke cleared and if I'm facing the windshield, at the top left area (passenger side), I saw marks of some liquid on the plastic covering there (sorry, I don't know the names of the car parts there), so I'm not sure if that got real hot and causing the burning smell, and if it's caused by that apparent liquid, I dno't even know what that liquid was or where it's leaking from... I believe the majority of the smoke was coming from there though..., so I'm guess it might be that, but not sure...

 

[DSK]

(Assuming that the fuse box on US spec cars is on the other side compared to UK spec cars), I am suspecting something along the lines of the fuse box area and the only liquid that should be around that area could be perhaps any washer fluid that may be leaking through the tubes.along the inside of the bonnet.

Can you describe the plastic cover in more detail or take it off and see what it conceals? Also describe the fluid, what colour was it? thick or thin? can you trace the fluid leak and see where its orignating from?

 

[abcxyz]

Well, I managed to take some pictures today. Looks like something is definitely leaking. Does anyone know what could be leaking and why would smoke come out only at higher speeds??

 

[Tom]

Well it looks like you have a bad valve cover gasket. The reason why you are seeing smoke at higher speeds is due to the leaking oil burning off on your engine block or exhaust.

You might want to check your spark plugs to see if there is any oil in the chamber as well.

 

[abcxyz]

Thanks for the reply! Hmm...how much should that cost to repair? Anyone have any idea?

 

[Tom]

The part is around $45ish and I'd say its a 2-3 Hour job. Its easy enough that you can take it to an independent shop instead of the dealer.

 

[chief]

Please accept my apologies for my "well not the first two, those were rather ignorant/infantile" response to your very serious query. Wish you had posted the pictures first, and 2nd reread your original "generalized, lack of adequate discription" of your original posted query.
I would write more but i don't want to continue being infantile.

LOL

 

[abcxyz]

The part is around $45ish and I'd say its a 2-3 Hour job. Its easy enough that you can take it to an independent shop instead of the dealer.

Thanks for the info and tips Tom! I'll get it fixed next week...

 

[abcxyz]

Please accept my apologies for my "well not the first two, those were rather ignorant/infantile" response to your very serious query. Wish you had posted the pictures first, and 2nd reread your original "generalized, lack of adequate discription" of your original posted query.
I would write more but i don't want to continue being infantile.

LOL

No worries...I don't expect much from jackasses that can't spell... peace out punk...

 

[chief]

Thanks for calling my 58 year old ass a punk. Just goes to show that youth is eternal in the minds of jackasses like myself. Hope your life continues to swim in the self inflated ego.