R129 500SL idle control valve issue / problem

[Makdissy]

Morning guys, I have a little problem with my 500SL 1992
When I start the car from cold it starts fine with around 800/900 rpm and as the car gets warmer the rpm start to go up and settle around 1200 rpm ( ain’t this suppose to be the other way around ) !!
Took the ICV off and gave it a good clean with a carb cleaner, not much luck there even though it did idle better for a few days and then back to square one
Just bought one on eBay and it’s doing the exact same thing
They are expensive from the dealership, so before I spend £600 on a new one is there anything I need to check or investigate before I waste my money if the problem isn’t the idle value !
Anyone had a similar problem before
All thoughts and tips are welcome
Thanks in advance

 

[d w124]

It isn't a pink car by any chance,is it

 

[Makdissy]

It isn't a pink car by any chance,is it

Finished painting ?

 

[RichardF]

Air leak? Try isolating the MOT/evap valve.

 

[alabbasi]

Is 1992 CIS or EFI? AFAIK, these cars had issues with biodegrable wiring harnesses from around 1992-1995 that caused all kinds of running issues. You might want to peel back the wrap and see what the wires look like.

 

[ray_hennig]

Is 1992 CIS or EFI?

I'd say CIS therefore not a bio wiring issue.

Of course, other wiring could pose problems.

Vacuum leaks?

RayH

 

[grober]

INJECTION PUMP MERCEDES M 119 (119960)

Parts for unit INJECTION PUMP MERCEDES M 119 (119960)

www.ilcats.ru

throttle linkage?