Air Marshall Eldritch

My car has been sitting in the garage without use for 8 days (out of town). It has not been very cold here, high 30's/low 40's for the overnight lows.

I had a Mobil 1 oil change not too long ago.

When I started the car for the first time yesterday, the engine was making a clattering racket like I've never heard before. I let it warm up for a few moments and the clattering subsided to a fainter sound. Then I slowly pulled away and drove about a mile to my destination. There, it seemed it was completely gone.

Could this be caused by the synthetic oil settling completely into the oilpan? I thought synthetics did not do this (unless you let the car sit for a very long time). It doesn't seem like a week would be long enough to allow the oil to completely dry out from the pistons.

mobinakhtar

Hi, I run Mobil1 full synthetic in my e420 and the vehicle usually just sits in the driveway because I use a civic to commute to work, and on weekends we are in the family minivan.

sometimes if it has been couple weeks or so, it does make this wierd sound like there is no oil in the engine, but it goes away completely after warmup. Unless the car is parked for two weeks at a atrech, I usually never experience this.

My Lexus ES300 (that does not see any action for months at a time) does a similar number on me, but not as noticable as the V8 e420.

Whitey

Hey R, which part of the world have you been hanging out lately?

Mine sits in an under covered parking lot for weeks sometimes (also due to travels) but fires up fine.....then again, we do have more moderate temperatures. Unlike you guys, I use an exotic brew, Selenia motoroil.

MB Enthusiast

I have a 1997 E-320 and if I leave the car sitting for more than 4 or 5 days I get the safe thing.

It sounds terrible.

I am in the northeast but this happens as much in the summer as in the winter.

I am not useing mobil 1

Lightman

Mine also makes a clatter upon cold startup. Strange

SmokeSilver

My '97 E420 does the same thing since I switched synthetic. It goes away about 1/4 mile down the road. Happens every morning now.

Lightman

Joking aside, it sounds like it could be a few things. One - which is kinda scary - it sounds like it's taking a while for oil to completely get everywhere in the engine. Though both of my vehicles are diesels, I'm sure there is a similar delay with gas engines. When I start the engine, it's noticeably louder for about 1 or 2 seconds, and then you hear it instantly quiet down as the oil makes its way through the engine. Possibly there is a restriction in the line, the oil pump is weak , oi filter clogged, or very possibly this isn't the problem. Another possibility is that it's valve or lifter noise. Depending on mileage, possibly a valve check/adjustment is in order. Has anyone actually called a MB dealer and asked to speak to a tech to ask them that question? It often amuses me how people fail to do that before they post on these forums.

SmokeSilver

The chattering coming from engine is coming from the belt. The place that services my E420 always steam cleans the engine on a major service. For some reason that caused the belt to make noise upon cold starts. I sprayed a little "Belt Ease" on it and it is now gone. Hope that helps.

ps-the steam cleaning also caused my #8 cylinder to misfire. Water had gotten into the cylinder and/or resister. The shop dried it out and that problem is gone too.

Lightman

Modern engines aren't supposed to have belt dressing applied. I had a similar problem on a tahoe. It turned out the belt tensioner was bad, was wiggling back and forth and giving me the noise. I'd check the tensioner when the engine is running and see if it's wiggling. Spraying it with lube is just putting a bandaid on the problem IMO.

BenzVince

Mine doesn't do that, since I don't use synethic oil. Just plain mineral oil as what the dealership speaks. My Maxima is my daily commuter car. One time i didn't drive my E320 for a month sitting, then when I start it up, it's fine but i get that Battery message. That kind of spooks me.

ninefourthree

the noise you hear is most likely the hydraulic valve tappets in the rocker arms. if it sits for long enough, the oil pressure in the tappets (aka lifters) will bleed off. (its not oil drying out from the pistons). this will cause a little slack in the valve train until pressure again builds up. the synthetic oil used in your engine will tend to do this more quickly because the oil is thinner at low temperatures that its mineral oil counterpart. the good thing about it is that, being thinner, it will get where it needs to faster. anyway, if your car is under warranty - rocker arms (with tappets) are often replaced for ticking or clatter noise. a new set of rocker arms will run about 900 dollars and about 6.5 hours of labor.

The Godfather

sticky lifters?

ninefourthree

no, lifters don't stick, they stop holding proper oil pressure.

The Godfather

Dump 1 qt. of oil out of the engine, replace w/ 1qt of ATF fluid, run for 500 miles, then do an oil change, and voila, no more ticking

jemmy

my 99 sat for 11 months and it does making that sound when started up...
changed the oil and it's gone...

Corp DL

I've noticed this phenomenon on my 430 too only once or twice. Kinda glad to know it wasn't just my car. I don't use sythetic which I've had considerable debate w/ myself on this issue; of whether I should or not.

Regardless, let me add another element to this conversation: on Christmas eve morning, here I was in Maryland where the temp was about 19F and I got the most brief puff of blue smoke (accompanied by an initial clank noise)!?!?! I've never gotten that before! I could smell a touch of carbon as well. I have 145K on this farily well serviced engine, but this worried me.

What's up with that?