3BadBirds

Hi!

Recently, my 190E has developed a problem when I try and start her the first thing in the morning. Specifically, the engine will crank then briefly sputter for a few seconds and then die. This cycle repeats itself about 5 - 10 times before she finally starts. Once the engine does starts it seems to run fine and will restart without issue as long as I don't let it sit for more then 10 hours or so. I recently did a complete tune-up but it did not fix the problem.

Is there some sort of cold-start system that primes the engine that could be failing? Any tests I can perform to confirm the culprit? Any help / advice would be appreciated!

Cheers!

tunayballa

What's included in your complete tune-up?

3BadBirds

plugs, wires, cap, rotor, air filter, fuel filter...

miaracing

look into the overload protection relay. its located behind the battery next to the fuel pump relay. its shinny silver and has a fuse on top of it. take it out and shake it. if it sounds like something is loose and rattling inside then its time to replace it and will more then likely cure your cold start problems.

tunayballa

While you are back there, you might wanna consider replacing the fuel pump relay also.

3BadBirds

Thanks! Someone else had recommended replacing this relay. Maybe I should give it a shot.

I'm not very familiar with this engine but was looking for some type of defective valve that is allowing the fuel / pressure to drop when it sits for awhile, like overnight. I've replaced similar valves on other engines I own when I have had similar symptoms. It seems that the engine just needs to crank for awhile to build up pressure and get fuel. As I mentioned before, once it does starts it runs fine and starts fine the rest of the day.

Thanks again!

ohlord

cold start valve and/or coolant temp switch will both cause your cold start symptoms
www.autohausaz.com has them.
ohlord

3BadBirds

I'm not sure if my problem is definitely related to the temperature. I still had problems starting her on a few of the relatively warmer mornings. Nevertheless, no matter how cold it was outside, she always started right up after this initial episode. The problem only seems to manifest itself after the car has been sitting for awhile.

Thanks!

ohlord

are not dependent on a cold ambient temp.They both function on cold start meaning ambient temp up to the point of the engines operating temp.So they need to be checked for proper operation.

KEELBOAT

Check the coil FWIW.

KEELBOAT

3BadBirds

I replaced the Overload Protection Relay and that seems to have fixed the problem. MY MB has been starting fine for the past week week. Hopefully that was the problem.

Thanks!