2015 ML400 idle changes when AC on vs. off
Thread Starter
Member
Joined: Apr 2012
Posts: 80
Likes: 7
2012 ML350
2015 ML400 idle changes when AC on vs. off
Recently my one year old ML400 engine idle would climb 200 rpm to 800 rpm when the AC is turned on and then drops back to 600 RPM when AC is turned off. It never did this before - the engine would aways idle at the same rpm regardless of AC action.
The extra 200 rpm is annoying in that the car lurches into gear and provides a rougher launch.
Is there a way to change the setting?
The extra 200 rpm is annoying in that the car lurches into gear and provides a rougher launch.
Is there a way to change the setting?
Senior Member
Joined: Sep 2012
Posts: 323
Likes: 31
From: Ottawa ON Canada
2015 ML350 Bluetec
If I understand your problem, it would be the same as the old USA carbed V8's, which were equipped with a solenoid to up the idle when AC is on. Going with that thought, my guess is there might be something off with your fuel management.... Your computer is reading something is lean(example), and is upping the rpm's to compensate! Maybe a visit to your dealer to discuss/resolve.
Thread Starter
Member
Joined: Apr 2012
Posts: 80
Likes: 7
2012 ML350
If I understand your problem, it would be the same as the old USA carbed V8's, which were equipped with a solenoid to up the idle when AC is on. Going with that thought, my guess is there might be something off with your fuel management.... Your computer is reading something is lean(example), and is upping the rpm's to compensate! Maybe a visit to your dealer to discuss/resolve.
