560 SEL random stalling

[ralphington]

My '89 560 SEL has started stalling randomly during the past 6 months. Happens at idle or at highway speeds. Hot or cold. Car will not restart until at least 1 or 2 minutes have passed. Then starts right away without hesitation. Very frustrating trying to prove it for the mechanic. However after much analysis, I noticed it stalled more during wet weather. Suspecting water in gas, I tried "dry gas" which sort of worked. Still had problems. One wet day it stalled 5 times on the way to work. I tried isopropyl alcohol as a gas line antifreeze and within 10 minutes no more stalls until the next wet day. Mechanic says there is no way I could be getting water into tank except with bad fuel. Since I use many different brands and stations, this does not seem to be the case. Could the fuel evaporator systems be letting in water when it pressurizes the tank? If so what is the best fix? If not where do I start next?
Thanks.

[pagodix]

Very similar to what happened to me in a 1968 280 sl, it was the ignition key and i solve it by changing the "innards" of the key.
Good luck

[Rahulio1989300E]

Well maybe it is not only water, but could be humidity that is causing this?
(So maybe it is electrical..)


Also....
Take a good look at your Idle Control Valve!