Uncontrolled Revving in Park/Neutral

[Iain Moone]

My 1988 300SE has recently started revving itself between about 800rpm and 1500rpm whilst idling in Park. If I blip the throttle it clears for a minute or so, then starts revving and dying again. It has also started stalling if i de-accelerate rapidly to a stop. Has anyone else experienced this, or have any ideas? Any input would be most appreciated.

 

[Andy]

Hi Iain

Sounds like one of the components of the KE part of the injection system is faulty or possibly the KE control unit its self.
Get it checked out.
Sorry to be the bearer of bad news.

Regards
Andy@www.mercedesservicing.com

 

[Neil Eglintine]

Yeah, sounds like the idle speed control box. I had this problem on my 380.

 

[Iain Moone]

I think I already know the answer, but I have to ask, Is it expensive ?

 

[Andy]

Iain,
No point me stating the plain obvious!!!

But before you jump in the deep end. Get it checked out!!

Regards
Andy

 

[Iain Moone]

Hi again, Good news. I took the car to my local Merc garage who removed the air filter housing and sprayed the Air intake with carb cleaner. Apparently there was something sticking (sorry i'm not at all technical) and that seems to have cleared the problem.