3-Series (E36)Chat relating to the BMW 3-Series from 1992-1999. Autodoodad
Specific models include: BMW 316i, BMW 318i, BMW 318iS/ti, BMW 320, BMW 323, BMW 320, BMW 324, BMW 325, BMW 328.
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was driving in front of a friend today and i reved my 93 318is to about 5 or 6K before shifting and he told me there was blackish/grayish smoke out the exaust... its got about 126K miles on it and i know it burns a little oil but does this sound serious? i asked him if it was just a tiny puff but he said it looked like a pretty good amount, maybe exagerating... i dunno
Have you had any warning lights come on? It doesn't sound serious, keep an eye on the oil level, maybe do the pedal trick to see if you have any stored engine codes. But unless it gets worse I wouldn't freak out about it too much.
Black smoke means the engine is running too rich (too much gas) and if it's at high revs then something is going screwy. won't affect the car too much that it's noticeable unless you're a real stickler about how your car runs, but get it checked out, it'll end up melting your catalytic converter, and whether or not your cat's melted down if it's throwing black smoke you'll definitely never pass smog in cali.
sorry kinda a noob to bimmers, can you fill me in on what the procedure is for my car to check codes please?
it wasnt reving high on its own, i was just gunning it on a straight-away...
could this possibly (god i hope not) be something like a head gasket or worn piston rings. anything of a serious nature? if its running rich should i check oxygen sensors or is there something else that might cause i rich mixture?
There's a DIY for checking the codes somewhere, I don't know the procedure. But as far as what could cause the running rich condition, there's a lot of things that can affect it. O2 sensor could be one, MAF, Injectors are sticking open...and on and on, just get it checked out by a local mechanic.
A blown head gasket no matter how small would cause a bit of a power loss mainly from a stand still to moving. If it's big enough you would see white smoke from the coolant that's burning.
A worn piston ring would cause more greyish smoke, and once again you'll lose a bit of power as the compression won't hold. Check the oil level, if it's dropping durastically and you don't have big leaks that could be it.
I do not have the link for the pedal technique to check the codes on my laptop. Once I get back to Jackson, I believe that I have the procedure there. Hopefully some one else will be able to enlighten you/us before then. Doing the pedal trick will tell you if it is an oxygen sensor or MAF or any other mechanical failure. Since I am from Arkansas and go to college in Mississippi, emmisions and smog testing is not part of my concern, so I really do not view this as a big deal, considering it would be legal for me to remove my catalytic converter and drive around.
It most likely is not a major mechanical problem. As noted above, a major mechanical problem would also give you a lack of power as noted above, rough idle, ect.
That's normal with aggresive shifting. BMW engines are typical; especially in manual tranXmissions when you shift just before redline that it puffs out a small cloud of smoke. What happens is the engine at that rpm builds up so much oil pressure that upon letting go of the gas pedal and disengaging the engine from the tranny to shift up it'll relieve pressure built up from the rpm through the exhaust port; hence the puff of smoke. I was surprised by this BMW feature because I thought it only affected older models. The new ones are just like that. I've seen it on the Autobahn enough times. After a hard run check and see if the inside of your exhaust is wet if it's just black and dry then don't worry about it. Your BMW is just saying I'm doing my job right and that's bringing you from Point A to Be in the shortest time possible!
That's normal with aggresive shifting. BMW engines are typical; especially in manual tranXmissions when you shift just before redline that it puffs out a small cloud of smoke. What happens is the engine at that rpm builds up so much oil pressure that upon letting go of the gas pedal and disengaging the engine from the tranny to shift up it'll relieve pressure built up from the rpm through the exhaust port; hence the puff of smoke. I was surprised by this BMW feature because I thought it only affected older models. The new ones are just like that. I've seen it on the Autobahn enough times. After a hard run check and see if the inside of your exhaust is wet if it's just black and dry then don't worry about it. Your BMW is just saying I'm doing my job right and that's bringing you from Point A to Be in the shortest time possible!
Do you have any links or way to verify what you have just said? I have never heard/seen this with my car. And I drive the crap out of my car.
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