My car has developed a issue at idle. It is a intermittent problem, it will be fine for a few weeks then out of the blue when stopping at a intersection. The RPM's will drop and it feels like the motor is going too stall, It hasn't stall completely yet. This has happen 4 or 5 times, The car is always at operating temp, It occurs after car was running at highway speeds. I am at a loss so any help will be great.

 

Sounds like carbon build up....

 

On a 2011? I thought the issue was corrected in MY 2010 and later.

 

I have a update on my problem, went to the dealership this morning. It is Carbon buildup. Service rep said that it seems to be happening to cars that are "Babied" , he said the car needed to driven more aggressively. They are going to do a top end motor cleaning along with 2 oil changes, since I am at 52000 miles they are doing the plugs too. The rep said that Lexus would pick up the cost of the cleaning and oil changes and I would pay for the plugs. I will up date when I get the car back. They did give me a GS350 F sport too drive, really nice car !!!!!