spark plugs replaced, now SMOKING UNDER MOTOR!!!

*1998 328i* *1998 328i*
i just replaced my plugs, now there's a burning smell complete with a little bit of smoke rising from under the motor, like near where the exhaust headers connect (NOT saying its the headers, because i cant see that far under). i have NO check engine light and the TEMP IS FINE (not overheating). smooth idle.

This is my daily driver and i need it by monday, so i need help NOW! cant call JG wentworth on this one =(

ill be checking this almost hourly fyi, so please expect me to respond promptly so we can quickly get to the bottom of this issue

thanks people!!

You probably have a leaky valve cover gasket. Not a big deal. They dry up, become hard, and start leaking after about 80-100k miles. My E36 needed to have the VCG replaced at about 100k, and the E34 I'm tending needed to have it replaced at 83k miles. I don't think it has anything to do with your spark plug change.

ok, you've slightly slowed down my nervous sweating.... but why would plugs incite this??

As I said above, I don't think the plugs had anything to do with it. There is no way they could have. It's coincidental.

Also, did you notice oil on your old spark plugs when you removed them? In addition to oil leaking down onto the headers, oil accumulating in the plug wells is another common sign that the valve cover gasket(s) have failed.

yes, cylinder 6 had a small dab of oil on the plug near the crush washer, and also a little bit down by the port!

Yep, classic signs of a dried up valve cover gasket. Fortunately, the parts cost about $30-40, and it's easy to replace yourself if you're a little handy with a wrench.

you have seriously given me some confidence. so THANK YOU!!

are the bolts in the BACK easy to unscrew? i know that its tough working on the back because its almost under the dash =/

Yes, everything is easily accessible when changing the valve cover. Here are a couple words of wisdom:

1) Use this DIY: http://www.dvatp.com/bmw/diy/valve_cover_gasket/
2) During reinstallation, use a torque wrench in INCH POUNDS (not foot pounds) or use a VERY light touch when tightening down the retaining nuts. Follow the guidelines specified in the tutorial above. The retaining nut studs are VERY easy to strip. Fortunately, they are replaceable if you do strip one, but that would be annoying. The OEM torque spec barely feels like it's tight enough, but that's the way it works best.
3) Buy 15 new retaining nut seals (LINK) in addition to the valve cover gasket set itself.
4) Use a little bit of oxygen sensor safe valve cover gasket RTV sealant ONLY in the locations mentioned in the tutorial above. Do not use sealant anywhere other than in those locations.

It took me a little over an hour to do it the first time. Here is a time-lapse video I made of me changing the VCG on my friend's E34, which is the same exact process as with your 328. The video cuts off after I get the old gasket out (battery died), but you get the idea.



(The part where I keep sticking a socket down into the plug wells and then wiping the socket with a rag was me extracting all the pooled up oil before removing the plugs)

If the car was sitting for a few days while you did the spark plugs, a good amount of oil may have leaked onto the manifolds and it all burned off on that first startup after. I've noticed that happen before.

im just going to have it installed. it'll take them 1.5 for $200. pretty reasonable, considering if something goes wrong, its on them.

and CJ, i started the car up right after they were done, but yea the manifold is the only thing hot down there, so i assumed some fluid was definitely coming into contact with them.

btw all, i ran my hand across the gasket with a glove. black oil all over it. definitely time to pull that gasket. thanks!
(car is 181k miles and still rolling > )

Originally Posted by dyer328

(car is 181k miles and still rolling > )

A mere child. My 325is=210k miles; and my 318is=233k miles

ZE, chances are his valve cover gasket isnt the only thing he needs as his valve cover itself is plastic(as can be seen in his video, and the one you showed your video is the earlier metal one) Id be willing to bet if his cover hasnt been replaced anytime within last 75k miles its due to be replaced as well.. i replaced mine at 165K, and when i held it up to a bright light could see all the cracks in it where light would shine through. on the plastic covers, once you start getting oil in the spark plug well it can be from a crack in the plastic around that well, and possibly removing coil packs and plugs (coil packs screw into metal studs on the plastic cover) it could have made the crack larger and letting oil drain out and down to his manifold. he might as well plan on saving the $200 he was going to pay someone to change the gasket for him and use it to get a new plastic valve cover (which come with a gasket set) and just take the time to do it himself.. He will be glad he did it himself in the end anyways.. hell if he had all the coil packs off he was half way there already.. lol

3) Buy 15 new retaining nut seals (LINK) in addition to the valve cover gasket set itself. +1 ZE... DO MAKE SURE YOU GET THESE <-------------------------

Dyer, also.. if you see any puffs of smoke come out of your tailpipe when your car has been sitting for a while that immediately goes away after a few seconds after you start it, its because your plastic valve cover has cracks in it..

Keep up with the videos guys. Visual learner Lol!

I've never heard of the plastic valve covers going bad with time, but I suppose it's possible. Lord knows the rest of the plastic on the E36 lasts about 10 days before becoming brittle. Anyway, the valve cover on my 328 (plastic) was totally fine when I changed the VCG at 103k miles.

Im sure mine was fine as well at 103k miles. although at 165k, it had cracks all in it...

Originally Posted by custm42435

Im sure mine was fine as well at 103k miles. although at 165k, it had cracks all in it...

FYI your sig is huge dude

Originally Posted by hornhospital

A mere child. My 325is=210k miles; and my 318is=233k miles

DO we really want to get into this? 328is with 256k miles.

Well, we had a high odometer mileage thread, but it died a long time ago.

My Geo has 348k. But that's not a BMW..........