When I turn my car off I have noticed a rattling noise that comes from the engine as it shakes to a stop. Any ideas?

 

Change the EGR valve. Also, have you done checking the troublecodes?


The PartsBin Blog

 

No I just noticed it tonight. I do not have a diagnostic device. I am not all that worried just don't like it.

 

If it's an automatic trans then I have no idea.

If it's a manual trans, try holding in the clutch when you turn off the engine, see if that makes a difference.

 

mine has also been doing this, but not with every shut off. i always have the clutch pressed in when i shut off. look forward to a solution. idk if my warrenty would apply to this since i'm sure the tech will say its normal.

 

Mine sometimes does this too. M/T, noticed that if I hold the clutch down, sometimes makes a difference, sometimes not....lol I haven't thought about it too much, no change in performance or running. Runs as smooth as my swiss watches, so not too worried....yet.

 

It sounds to me like mild classic dieseling. Are you familiar with dieseling? It's when the engine runs on after the key is turned off, usually the engine shakes like you describe. the rattling noise comes from preignition just like spark knock and sounds like a diesel hence the title. Check out this for the description and possible cures.

http://en.wikipedia.org/wiki/Dieseling

There's a valve on most cars that turns off the fuel supply immediately when you turn the key off so the car won't run on, if it's defective and the engine has hot deposits within the cylinders, or the spark plugs have deposits, they will ignite the fuel even if the key is off. Good Luck. Keep us posted.

 

I car does this as well (M/T) and I have heard of others on another post that have this problem if you want to call it that. It used to concern me but no I barely notice it. It doesn't seem to affect anything.

 

Ok, so I have the same Knocking during turn off, and since one of my good friends works for chrysler I brought it to his shop.

He thinks it might be the crank bearings... (Bad News)

Check to see if you notice this... Try to listen for a knocking sound when you pull up in your driveway. It is very quite cuz our car is so loud, when you turn off the car it knocks...

When you dont hear the knocking during idle, there is no knocking during de-ignition. (Yes I just invented that word)

we are gonna throw it up on the lift and figure it all out this week

 

Check the belt tensioner. It might have a weak spring. Check the simple things first!

 

common symptom of a timing problem ...

 

The 112 engine has no know crank bearing issues. It seems like most of the people that hear this are M/T owners and that would point more to the throw out bearing. In some cases, if heard at idle, could be a bad catalytic converter.

 

car is designed to run on high octane fuel ... in colder weather, using a low octane fuel could potentially be another cause of this problem

 

After some investigation, I think you got it right... Throw out bearing seems to be the problem.

Notice the rattle will only occur while the clutch is depressed.

 

Aarghh! Severe idling rattle after freeway running, then goes even louder at switch off as the engine shakes to a halt. Sounds very much like loose baffles inside the centre of the exhaust system to me. Has got louder over last 6 months. Now embarassing at lights. No noise when cold. I don't think it's in the engine. No error codes. These Crossfire exhausts are probably non-Mercedes. There have been old threads on this noise, but none says what the outcome was. Please, somebody must have solved it. 2005 coupe automatic with 50,000km = 31,000 mls. Please enlighten us. Please. No doubt my New Zealand Dealer will recommend a new exhaust for $4000. And then stuff something up. Aarghh!

 

Your converter is shot ! In the U.S. this is covered under warranty for 100,000mi. Don't know about New Zealand.

 

its the throw out bearing, mine chatters with the clutch released at shutoff. not when i have it held in at shutoff

 

so if this is what everyone and I (M/T) are experiencing, is this normal or something that needs to be fixed?

 

OK, guys. It IS the catalytic converter, but it is NOT shot, only loose in it's housing. My dealer showed me a tinkly one off another Crossfire, and said it's a German problem, also afflicting Mercs and Audis.
He said, "it's thousands to replace", and I replied, "how many thousands?" He said he'd let me know.
So I drove off to a surf beach to catch some waves, 1.5 hrs each way, thinking over and over that God would know exactly where and how and with what to pinch the steel casing to grip the platinum converter inside it.
Well of course God can always exceed a mortal's aspiration, and He doesn't need help. Back home the noise was gone, and is still gone two weeks on.
The dealer got back to me with $NZ2804 (=$US1450), and I told him I'd think about it. I have faith that I will never have to fix it.
Best Regards, Jim in New Zealand.