I have a 1995 E320 estate, petrol, 135,000 miles which has a couple of possibly inter-related problems.

1) Intermittently, when the ignition is key is turned - the engine simply will not turn, although the dashboard lights come on etc. Turn the key to the off position and back again and the engine may then turn over and fire. It can take 3-4 key-turn cycles to get it to "wake up" and turn over. Can do this with the engine cold or warm. Does it with 2 different keys.

2) Also intermittently, I turn the key, the engine IMMEDIATELY turns over (as you'd hope!) but will not fire, or give even a hint of firing - not a cough, splutter or hiccup. It will normally sit there and refuse to fire, even if you turn it over 10 times etc. Come back in half an hour, turn the key and it fires immediately. Seems to do this more when the engine is warm, but that may be my imagination - I think it's done it ocassionally from cold , but seems to be mainly when warm. Does it with 2 different keys

Anyone have any insight on any of this?

Thanks...

 

Usually, for the #2 symptoms, it would be / could be the crank position sensor.

But that has nothing to do with #1 symptom. maybe two different problems?

 

First, I'm not a mechanic, so these are just my experiences.

First I would check the battery terminals to make sure they are clean and the ground is good.

Second, I would check that no moisture is getting to the electronics behind the battery.

One similar problem on my car turned out to be a loose wire on a connector which I found by moving wiring a little while the car was started (watch out for the fan blades...etc.)

Another, similar problem on my car turned out to be the neutral safety switch.

Others may have better suggestions.