Water In Gas / Bad Head Gasket?
 

Hello MBer's
My '91 190e 2.3 has a peculiar intermitent problem. It runs and idles perfectly, then at times during acceleration a puff of blue/white smoke billows out the tailpipe and I get some pinging. I get it home, idle it for awhile, and the smoke persists. So, I check the plugs, all are wet, can't tell if it's water, gas or fuel. After installing the plugs, I let it sit overnight. I start it up in the morning, everything works fine. A week later, the same scenario.
So, after much thought, I am assuming it's the head gasket. But if it was, why wouldn't it smoke all the time. Then I considered maybe there's water in my gas. Would this cause the same symptoms as a leaky head gasket?
Randal

I have had a faulty ignition coil cause this.

I have had a faulty ignition coil cause this
 

Hi Benzmac,
Thanks for the reply. Not to doubt you, but why would the coil cause the smoke and pinging?
Randal

<all are wet>

It would be hard to imagine a head gasket scenario which would cause this. I would look for a problem in or before the intake manifold, either raw gas leaking in or perhaps a coolant leak in a preheater?

I suppose incomplete combustion from a failing ignition coil could cause an unburned fuel problem, or anything else affecting all cylinders equally.

Steve