Hi,
my 2007 IS250 RWD Automatic sometimes especially when it's warm (both the car and outside temps) and I get to a stop and the car is in Drive or Reverse the revs start irratically going up and down between 700-900 rpm and the whole car shakes. When I turn on the headlights or put the car in Neutral the rpms settle at normal idle speeds. When I take off car is driving normally. What could this be ? MAF is cleaned, Throttle body is cleaned, fuel additives on a regular and the alternator seems new, spark plugs are also new. No lights on the dash. Bad maf ? Carbon build up ? Weak battery ?
Thanks in advance
Spoiler2007 IS250 irratic idle
What do you mean the ‘alternator seems new’??
Load test your battery & alternator before all else & check if they’re both working normally.
Have you checked vacuum? If fuel and spark are good, then then only thing left to make bang is air right?
Well, I was thinking it is more of an electrical thing since it returns to normal when the headlights are on and/or the car is put in Neutral.
Have you scanned for codes yet to confirm issues then?
- bump