Hello Everyone

I have a 92 MB 190E 2.3L with a starting and running issue.

Basically when cold, it starts but during cranking the rpm needle will sometimes erratically bounce up to approx. 5k rpm then it starts....

Once running it will run at 500rpm (about 250rpm too low) and shudder until the engine temp needle moves a little bit.

I changed vacuum lines from idle air control valve becasue the car was idling too low before at all times.

Now it idles fine when warm but it has the above problems.

I am wondering how to tackle this problem.

So far:

1. Checked OVP, fuse fine



2.Swapped OVP for another one, no difference

3.* Idle control valve: (bet intake cyl 2 and 3) checked, its clean and the little valve opens when engine cold once I turn ignition key.

4. Replaced few vacuum tubes/ hoses from idle control valve to the T split and checked for cracks etc...

5. Cold start valve? How to check?


*I am not sure how to properly diagnose the cold start valve, I only checked that it opens and closes


All these parts are pretty $$ and I do not want to start replacing them for no reason..

Thanks for reading