For a service manual, Mercedes recently posted them all online free for use, here is a link to the 124 manual:

https://www.startekinfo.com/StarTek/outside/12264/?requestedDocId=12264

https://www.startekinfo.com/StarTek/outside/12264/Program/matrix.htm

As for the high idle issue:
My 190E would do this from time to time. I actually think its somewhat normal for the car to high idle (~1000rpms) on a cold-start. Once I get the car in gear and driving the idle returns to a normal 700-800 rpms.

__________________
Cruise Control not working? Send me PM or email (jamesdean59@gmail.com). I might be able to help out.
Check here for compatibility, diagnostics, and availability!

(4/11/2020: Hi Everyone! I am still taking orders and replying to emails/PMs/etc, I appreciate your patience in these crazy times. Stay safe and healthy!)


82 300SD 145k
89 420SEL 210k
89 560SEL 118k
90 300SE 262k RIP 5/25/2010
90 560SEL 154k
91 300D 2.5 Turbo. 241k
93 190E 3.0 235k
93 300E 195k