2009 S63 AMG P0171 CEL




If it was my car, I'd tackle (1), (3) and (4), in that order -- all cheap and good to do in any event. If not that, then I'd suspect either the fuel pump or the ECU, both expensive fixes. By the way, how's your battery? Benz SClasses are notorious battery hogs -- faulty batteries don't adequately power the computers, leading to all sorts of crazy faults that make no sense. But the fact that it's heat dependent might say spark plugs.
Hope this helps. Good luck.
maw
When you say they have been updated to SLS ones - should I look to purchase ones that are spec'd for the SLS specifically - and rule out any chance of being given the same flawed variety in the S63?
Thanks for you help.
I seem to have read that many people have complained about the intake manifold bolts on the M156. Are there replacement (steel or titanium) aftermarket units anyone can point me in the right direction to? Or is it just a better idea to remove them, add some Loctite and torque them down to spec again?
The one thing that I can't understand is why the car is more prone to stalling when hot than when cold. If it is the manifold gasket/bolts, perhaps its due to metal expansion - causing a greater gap and letting more un-metered air in?
Really appreciate the feedback.
I seem to have read that many people have complained about the intake manifold bolts on the M156. Are there replacement (steel or titanium) aftermarket units anyone can point me in the right direction to? Or is it just a better idea to remove them, add some Loctite and torque them down to spec again?
The one thing that I can't understand is why the car is more prone to stalling when hot than when cold. If it is the manifold gasket/bolts, perhaps its due to metal expansion - causing a greater gap and letting more un-metered air in?
Really appreciate the feedback.
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Now that your MAF is installed properly, I'll go back to my original statement. You shouldn't have any problem with K&N filters on this car. They don't let in so much air the computers can't adjust.
At the risk of pointing out the obvious, for all you know all the other people reporting these problems after installing K&N filters made the same mistake you did (improper MAF installation).
Although your experience moved me further to going back to factory filters where I have K&N filters. If the goal is clean, cool, compressed air passed by properly reading MAF sensors and into the engine, I'm failing to see how adding oil to "free flow" filters aids that process. Don't get me wrong, I'm not railing against K&N filters. But I think they may have a better home in old Detroit Muscle than in any modern MB AMG (or BMW M) car.
Enjoy!
maw




I have K&Ns on my M3 and on my 500E, both courtesy of the prior owners. But I'm starting to think to go back to stock, at least on the M3.
maw





