2003 ML320 64k miles, recent check engine light, got the codes read at Autozone and it showed a misfire to #3 &#5, I took the cheao way out, at least thought that in the beginning, changed the plugs, all 12 of them (at $16 a pop), changed all fluids etc, the old plugs looked pretty bad, once I started the car up it ran real good, had the code cleared and it was gone for a few days. Then it started smoking again on cold starts and sometimes has an intermittet large puff of smoke out the tailpipe (white /grey in color) all fluids seem to be full and uneffected (thought it might bea blown head gasket but not loosing coolant or oil) talked with a tech who is to be the best in the area, he thinks it has a leaking valve cover gasket, I know things have changed in the past 20 years but that doesnt make any sense. PLEASE PLEASE HELP!!! get the wife off my @$$...

 

is there a sludge on the oil filler cap? then...

overhaul the engine.

it is burning oil.

replace the piston rings and valve seals.

sooner or later, the oil will clog/damage the catalytic converter.

 

More info, thanks for the reply's. No sludge on the oil cap, actually very clean, the service on the car has been performed very frequently since the car is not driven much. The smoke is very light gray and has no burning oil odor, smells more like a carbon type smell but very very faint, thos occures at intermittent times, on start up sometimes, the about 10 miles into a ride just a puff and it's gone for 30 miles. The clogged converter sounds more like what the problem may be but getting a good flow of air out the exhaust. Not loosing any fluids at all, actually marked the levelsa with a sharpy and paint pen to verify. A mechanic said it could be possible the egr cooler is leaking and when it opens that could be the intermittent smoke, this is a gas engine so I believe there is no egr cooler. I've got to figure this out, if the motor needs a rebuild fine I can pull is and rebuild it fairly quickly, I just don't think that's the problem. Any further assistance is appreciated.

 

reconfirm by removing some spark plugs.

see if the tip has some carbon build-up. (which can cause misfire too).

 

1. Start by telling your wife that you have enough problems without her bitching

2. Take your tech's advice and change the valve cover gaskets

3. If this does not work, it could be a head or intake manifold gasket.

Best of luck,

Will3hawks