For the first 20 -30 seconds when firing up from cold I get a rattle which I cannot pinpoint, its either from the exhaust or engine but disappears once the revs drop. Have done a google search and dont think its anything to worry about as could just be the oil getting to parts of the engine but would like to know if others think its the norm, cheers Colin

 

Hi Colin,

Has the noise started since your oil change??

Zak

 

Mine has been doing that for 10 years. I think it's normal

 

I'm not really sure Zak if the noise is since I changed the oil because I changed it within a week of owning it. Also I only happened by chance to hear it the first time when I had put the roof down in the garage and started it, when the roof is up its not noticeable.
Reassuring to hear yours has always done it Witchal.

 

Sounds like it could be your CATS, they are prone to breakdown inside which will coarse such a rattle. get under the car and give them a good shake, if it is one or both you should hear the rattle.

 

If it was the cats would it still stop after 15-30 secs?

 

Could be they heat up and expand, therefore the rattling stops.
Just guessing.

Also could be the air injection blower, it runs for about the first 20-30 seconds after startup.

 

I had a 3800 engine that rattled on a cold (and sometime warm) start up. Was told it was piston slap. Did it for over 100k miles before I gave it to my brother in law. Am told it is still running fine.

 

Thanks for the info, as long as its not going to get any worse I can live with it. Was beginning to wonder if it was because on my last service they put in 5w 30 and not 0w 40, I have never been so interested about different oils since getting the crossfire and have put any old crap in other cars lol

 

IF its not on one of these lists, I'd never go back to them again.

MB 229.3 - Multigrade engine oils (Specification 229.3) - Mercedes-Benz Specifications for Operating Fluids

MB 229.5 - Multigrade engine oils (Specification 229.5) - Mercedes-Benz Specifications for Operating Fluids

I have a rattle, but it's either the idler pulley or water pump - gotta get that tended to before the fall Dragon....

 

My local Tire Kingdom will do a oil change & filter with all the extras for $66.89 plus tax. They use Valvoline full synthetic which is MB 229.3, .31, .5, & .51.(see http://www.valvoline.com/pdf/synpower.pdf) . That is a bit less than the $148.15 the Chrysler dealer charged. They have done other things I've needed properly.