Stop/Start
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Member
Joined: Mar 2003
Posts: 188
Likes: 78
From: Toronto, Canada
GLC300 (mine) GLK250 (wife's)
Stop/Start
I've always been careful to let a turbo engine idle for 10 or 20 seconds after a highway run to allow the turbo to spool down. The reason is that a turbo can spin up to 150k RPM and shutting the car off immediately cuts off oil flow while the turbo is still spinning at a high rate, this increases wear. Also, engine oil helps cool the turbo and after a high-speed run, the turbo is hot enough to "cook" the remaining engine oil if the flow is cut off. This increases deposit build up..
Seems to me that auto stop/start can accelerate turbo wear and carbon build up by repeatedly cutting off oil flow to the turbo. This would be particularly problematic on county-type roads where speeds are close to highway levels but there are occasional stop signs and traffic lights.
From what I gather, vehicles with stop/start often have electric an coolant pump to keep passengers warm during stop cycles. However, I haven't heard of electric oil pumps outside of racing and specialized applications.
There have been lots of "innovations" introduced to meet fuel economy standards (e.g. deleting the spare tire). Stop/starting a hot turbo engine might be one of these fuel-saving initiatives with unintended consequences.
Does this seem logical to anyone else or am I totally off base?
Seems to me that auto stop/start can accelerate turbo wear and carbon build up by repeatedly cutting off oil flow to the turbo. This would be particularly problematic on county-type roads where speeds are close to highway levels but there are occasional stop signs and traffic lights.
From what I gather, vehicles with stop/start often have electric an coolant pump to keep passengers warm during stop cycles. However, I haven't heard of electric oil pumps outside of racing and specialized applications.
There have been lots of "innovations" introduced to meet fuel economy standards (e.g. deleting the spare tire). Stop/starting a hot turbo engine might be one of these fuel-saving initiatives with unintended consequences.
Does this seem logical to anyone else or am I totally off base?
