I am having problem with a high idle on my 2.6. I just replaced my water pump, and instead of taking virtually the whole front off the car, I unbolted the intake manifold. After I replaced everything, I put all the sensors, and their plugs back. I have since rechecked everything several times, and also tried adjusting some things, but I still have an idle that sits at about 2100 rpms when warm.

Any help appreciated!

Check for loose vacuum lines and vacuum leaks.

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/showpost.php?p=831799&postcount=13
http://www.peachparts.com/shopforum/showpost.php?p=831807&postcount=14

Already checked!

Check this thread for Duke 2.6's comments about the throtle position sensor.
http://www.peachparts.com/shopforum/showthread.php?t=108133&highlight=high+idle

and some more related reading...
http://www.peachparts.com/shopforum/showthread.php?t=96638&highlight=high+idle

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/showpost.php?p=831799&postcount=13
http://www.peachparts.com/shopforum/showpost.php?p=831807&postcount=14

that happened to my 190e2.6 as well, and it was diagnosed as a faulty throttle linkage microswitch. Changing the microswitch solved the problem.

this is a small switch (hence micro-) that is situated in the area of the throttle linkage. You have to remove the air filter housing to get to it.

i hope this helps

Actually, the problem turned out that the microswitch wasn't close enough to the throttle linkage anymore, and even tho it was being activated and initiating idle, the little arm was not pressed enough to fully calm the idle all the way down