amgmercedes

My W124 E420 is emitting white smoke from the exhaust. Its most likely water since my hands get wet when I put my hands near the muffler tips.

Most of the time there is little or no smoke, but lately it does produce some major smoke once in awhile. Ive noticed the smoke when idling, cant really tell if it also happens at partial or full throttle since I gotta keep my eyes on the road.

Have yet to check for coolant loss since Ive just replaced water pump and topped of the expansion tank.

Head gasket? Valve seals? Car has 56,000 miles.

How do I check? Take a look at the plugs? If the car is burning oil, I know the plugs will be oily, what about if its water its burning?
What signs should I look for?

I dont know if these are in anyway related to the above problem, but I have noticed the following problems:

1.) ticking noise in the engine, valves? lifters? (had this for quite some time already)

2.) exhaust gas smells bad, smells like engine is running rich. Punget smell thats kinda irritating on the nose and eyes. (started to notice this a few weeks ago)

Thanks.

Kestas

Sounds like a headgasket. You mentioned the water pump was replaced. Did you have an episode of overheating the engine or running out of coolant? Can you smell coolant in the exhaust?

Valve stem seals would have a different pattern. You'd get a puff of smoke at startup and again after every stop. It'd be constant and predictable.

One way to veryify coolant leak into the combustion chamber would be to remove the spark plugs. One (or more) of the plugs would be uncharacteristically clean and maybe wet.

amgmercedes

There was a case of overheating sometime ago due to the radiator's plastic end caps cracking. I believe I am losing a bit of coolant.

I do get a puff of white smoke upon start up when engine is totally cold, but not everytime. And I only notice the white smoke whenever the car is moving slowly or at a stoplight since those I are only times I can afford to look at the rearview long enough and not risk getting into an accident. But then, I dont see smoke everytime, just once in a while.

Will check the plugs later.

Should I get a replacement head gasket or just order an entire top overhaul gasket set?

Would you happen to have the part numbers for the head gasket, valve stem seals and top overhaul gasket? for a 93 400E?

amgmercedes

Just checked plugs, they all looked fine to me. No oil or anything.

Kestas

Now it's beginning to sound like valve stem seals and guides. A blown head gasket would be hard to miss.

With leaky valve guides, the high vacuum condition during idle pulls oil past the guides. When you accelerate, this oil gets burned up, hence the puff of smoke.

amgmercedes

Wouldnt the plugs be oily if this was whats happening?

Kestas

Not necessarily. I owned a Chrysler with the 3.0L mitsubishi motor famous for leaky valve guides. I got lots of smoke with no ill effects to the spark plugs.