Who Runs Down Their Turbo ?
Thread Starter
MBWorld Fanatic!
Joined: Mar 2008
Posts: 3,714
Likes: 56
From: 1 hours drive north of Sydney Australia
2007 W204 220CDI Classic Sedan
Who Runs Down Their Turbo ?
I believe it is sensible to idle a turbo engine for a brief period instead of turning it off immediately after running at highway speeds or towing a heavy load. It at least gives the turbo a little time to run down with the bearing oil supply present & for the cooler exhaust gas to normalise the metal temperatures. I do not think it is necessary when idling around town at 60 Km unless you are accelerating like an 18 year old.
MBWorld Fanatic!
Joined: Apr 2003
Posts: 4,781
Likes: 3
From: Boston
'05 A4 1.8TQM6
Always a good idea to let a turbo cool down after running it hard/spirited up to your destination. Shutting it off immediately could result in oil cooking on your turbo, leading it to it's death slowly.
Even when I'm easy on my car up to when I park, I give it 10 seconds to cool down. But if I've been in boost, I'll let it run for a minute (or longer, depending on how hard I ran it) before shutting her down.
Even when I'm easy on my car up to when I park, I give it 10 seconds to cool down. But if I've been in boost, I'll let it run for a minute (or longer, depending on how hard I ran it) before shutting her down.
MBWorld Fanatic!
Joined: Jul 2007
Posts: 1,609
Likes: 2
From: Wyckoff, New Jersey & Alphabet City NYC
86 190E 2.3-16v, 92 500E, 03 CL55 AMG, 08 E3504M Brabus
Similar situation for SC engines? I can't say I always let a cool down period before shutting off...maybe I shoud....
MBWorld Fanatic!
Joined: Jul 2007
Posts: 1,609
Likes: 2
From: Wyckoff, New Jersey & Alphabet City NYC
86 190E 2.3-16v, 92 500E, 03 CL55 AMG, 08 E3504M Brabus
haha theres no way I'd put anything aftermarket like a turbo timer in my car. I'd rather sit and wait but I'm sure I wont 
Trending Topics
Senior Member
Joined: Sep 2004
Posts: 268
Likes: 0
From: orange county
99 DC2, 08 C350
my response was a more general turbo response
in your case, superchargers generally don't have to be cooled. In most applications, the SC has its own oil supply.
Also, the internal bearings don't see nearly as much heat transferred through the intake manifold as a turbo will via the exhaust mani.
MB World Stories
The Best of Mercedes & AMG
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
MBWorld Fanatic!
Joined: Apr 2003
Posts: 4,781
Likes: 3
From: Boston
'05 A4 1.8TQM6
Turbos even on new cars today still need a cool down if driven hard up to your destination or long periods of time. If you run your car hard up to before you stop and it's a oil cooled turbo, by shutting it off immediately the oil will "coke" the turbo aka, "coking your turbo". The extreme high temps will cook that oil that's sitting there (since you've stopped the engine, no flow of oil to cool it down) and cause bearing failure.
By letting it run for a minute or few minutes, the oil cools down the turbo so that when you turn it off after that, the turbo is cool and won't cook the oil. Btw, there is a turbo cool down section in my owners manual.
By letting it run for a minute or few minutes, the oil cools down the turbo so that when you turn it off after that, the turbo is cool and won't cook the oil. Btw, there is a turbo cool down section in my owners manual.
Senior Member
Joined: Sep 2007
Posts: 366
Likes: 1
2008 C300 SPORT (white)
he is not talking about an aftermarket turbo, he has the european version of the car C200 CDI, it comes wit a factory turbo, Germans call (Kompressor)
