Strange very difficult start

Hi all, I'm puzzled why my '89 300e would not start today after running just fine for a couple of km. Admittedly it had been sitting for 10 days or so
in the sun (well over 30C several days) without being used. It started reasonably well, ran just fine a few km, I then parked it for about 20 min and on trying to start it much sputtering and weak firing etc. The gas cap came off without vacuum, after it ran again, with the odd sputtering, it is now apparently just fine again when I tried it after supper.... is this a vapour lock sympton? If so, why did it run initially though??
cheers, guenter
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Most likely due to vapor lock. The fuel system ought to be checked to ensure it retains full pressure (pressure prevents liquid to gas transformation).
The reason the motor started well when cold was just that - it was cold, so the fuel was in its liquid form.
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thanks to you and Tiger for that, appreciated. I had in the back of my mind that that vapour lock problems required 'Death Valley' kind of temperatures not low 30's C (ie 90's F). Moreover, why would the engine have worked just fine for a few km ..... wouldn't that have purged the whole fuel system of any trapped gas vapours ?
cheers, guenter

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It is the engine heat that cause vapor lock when you shut down.
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    Ahh, of course. thanks.
cheers, guenter
ps to check the accumulator, it's just in front of the rear passenger side rear wheel, behind the fuel pump and filter if I remember correctl? right?
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Vapor lock is created by heat - the heat of a hot engine; higher than "normal" ambient temperatures are the straw that breaks .......
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thanks, I imagine - as you say - higher ambient temperatures along with old age. Consequently, I clearly need to follow up on the fuel pressure after engine shutoff. I'm getting more and more indications that at 235k km ie 150k miles, the car is beginning to show it's age. I'm glad that I was driving and not my wife.... at least this way I got supper.
what to buy, what to buy in terms of a nice about 3 to 5 year old, new to me, MB for the wife.
cheers, guenter
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Yep. Most likely vapor lock. Check your fuel accumulator to see if it is bad. Pull out the rubber hose side and if fuel keeps coming out, it is bad.
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