1991 190E starting problems
 

Hi my 190E starts ok when cold when it idels down it runs rough and then it dies. It will not start unless I crank it for along time and if it does start it runs vary rough! Can anyone help please.This car is a fuel injected 2.6L and it has me pulling my hair out. Sometimes it runs properly but lately not so good their are a lot of sensors dont know witch one to check first?

may be the water temp sensor problem!!!

Lots of possiblities, but I'd start with cleaning the idle control valve and checking for vacuum leaks.

You are probably going too lean warm (this can be the temp sensor, too) so the engine won't run. Hard start hot is also a symptom of over lean condition since there isn't enough fuel being delivered to get good igntion at cranking speed.

Don't adjust the idle mixture until you have found and repaired vac leaks, or it will promplty start running rich instead.

You may also have a bad coil that stops working properly when hot, but I'd start with fuel mixture.

peter