PeachParts Mercedes-Benz Forum - cold start valve vs. ovp

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Quote:

Originally Posted by duxthe1 (Post 2039618)

"Then why do they seem to have such a hard time cold starting and idling?? (Maybe I am just bitter....) "

The cold start valve is a very simple part of a complex system. There is a reason the newer cars don't have CIS injection. Most manufacturers gave up on it well before Mercedes did.

Thats reassuring.... :o :eek:

I do have the right spark plugs in mine, old ones were Champion Resistor plugs....it improved massively with the new plugs. Bosch H9DCO from the dealer.

Mercedes "gave up" on CIS early, then like Volvo, realized that there is no limp-home mode in the L-Jetronic, it's either go or no-go. The decision was made to stick with the electronic version, the CIS-E with the Lambda to ensure that their cars would always make it to their destination. A good decision IMO as I spent plenty of time helping friends get their L-Jetronic cars to my garage to be fixed during that era.

The advantages of the later system are efficiency and volumetric efficiency, or power/mileage/emissions.

CIS is a very good system for what it's intended to do, and reasonably reliable. Since it only was installed through the early '90s, we're talking about cars that are at least 15years old, to have a few maintenance issues is IMO not unexpected at this point.