out of high idle hell

Today was the day of liberation of high idle,I talked to a very nice man at Fernandina Beach Florida today,HE IS A M.B. MECH. he showed me a metal box on the top of the idler control, it is a round plug like on top, that over time works upward--I taped it back in about one eight inch, i made sure all vacums were tight and then i could idle my car,i called him and told him it worked, and thanked him also. Dennis

[RickM]

What year is your car?

Is this round plug near the Idle control module which is behind the glove compartment?

....and you merely reseated the plug?

My car is a 1979 450sl, no it was not behind the clovebox, it was in front of the intake houseing--the ilde control,i think, Dennis

[jr811]

My 79 450SL has a high idle problem which I can't solve.
Is the "idle control" which you taped near the idle speed adjustment screw?

Yes Jim it is, just to the left of it--Dennis

[fasted]

The idle speed screw is what you are "taping" down. The screw is plastic and held under tension by a light spring to avoid loosening.

NO--- just to the left of the the idle screw, a round metal box, like there is a plug-like on top of that. good luck Dennis

[jr811]

Dennis - is it the supplementary air value also called the auxiliary air value ( I believe) which you taped back. How hard did you tape ths " metal box)

Jim 79 yellow 450sl

I taped the round plug-like on top of the metal air box,I used a rubber mallet to tap it, just enough to tap it back about flush with the top of the metal unit.I was careful not to beak it. good luck, later Dennis P.S. i hope the weather clears-up here for the superbowl

[ctaylor738]

Did you mean "tapped?"
:-)

YES-TAPPED , it works loose over the years or( up) Dennis

[ljmauricio]

Sorry Dennis, but one more time. Would you describe the location of the module you are "tapping" down. I'm looking, but not seeing. Perhaps my problem is my engine is 500, not 450. My problem is erratic idle. Sometimes 700, sometimes 1000. Changes from stop lite to stop lite.

[ctaylor738]

Completely different system. You have an electronically controlled idle. Dennis is talking about the temperature controlled idle valve in the earlier engines.

You are correct Chuck,1979 450SL,early model: Dennis