Which one is it?
 

Tried to do this one without asking but........
Did all the 'noobe' searching that I could on the problem I am having (rough start up idle) and have narrowed it down to a possible faulty OVP. In my searches I found where the location of it is, but am uncertain which one it is. I took a picture and I assume it is either the chrome one, green one or white one. (1990 500SL)
Thanks for the help on this one.

http://www.members.shaw.ca/m_janzen/OVP.jpg

Doesn't a 1990 500SL have a M119 engine? If so - I think I remember reading that it doesn't have a dedicated OVP relay.

Please check to make sure before you replace. I could be wrong.

Troy
1995 E420 93k

Well then I guess I'm back at square one on my cold start rough idle. Found this post which seems the same as what I am so I guess I'll start looking at a possible injector problem.
http://www.peachparts.com/shopforum/mercedes-benz-sl-discussion-forum/78928-idle-hesitation-problem-solved-i-hope.html?highlight=500sl+idle

Car runs/starts perfect after it warms up. Only happens for 30-60 seconds at first (cold) start.

Nope no OVP...that way when something goes wrong it takes your EZL w/ it..sharp engineering on MB's part w/ that one.. That aside, how many miles on your SL? These are known for harness issues as well as throttle slide's acting up w/ age.

Jonathan

Just turned to 69,000 kms last week which is around 43,000 miles.

Problem solved.
Went to the free mechanics clinic and ad the evaluation done on the car. They quickly diagnosed the multiple problems I was having. They stated this was all because the tow company that delivered my car boosted it.

Problems:
1. The ABS light was on.
2. The cold starting and rough idle problem.

Solution:
A $3 fuse that protects the Over Voltage realy (see pictures)

They replaced it at no charge and sent me on my way. Total cost of everything...... ZERO. Wow, am I ever pleased with this dealershipd service (Lone Star Mercedes in Winnipeg)

Here are a few pictures of where the relay and relay fuse are located in case someone else runs into the same problem.

Remove the 5 screws holding on the cover on the far left top engine area.

http://www.members.shaw.ca/m_janzen/fuse1.jpg

The over voltage relay is right in the middle with a clear plastic top

http://www.members.shaw.ca/m_janzen/fuse2.jpg

The plastic top pops up and the red fuse pulls strait out

http://www.members.shaw.ca/m_janzen/fuse3.jpg

Please repost - your pictures didn't make it up.

Troy
1995 E420 93k