i would think the car shouldn't shut off the engine once you've past a certain speed (in this case it seems 30km/h)- even if you do press the Start/Stop. Once you cut off all power you're left with whatever vacuum pressure is in the brakes and after pumping the pedal a few times, there'll be no more additional stopping power.. add to that the steering locking system..
but the engine cutoff while driving is a serious issue.. btw, do you wash your car yourself or send it to a car detailing centre? the problem with our car is that the flippin' ECU is mounted just behind the battery and isn't very well protected against the elements (actually there's almost no protection??).. so avoid washing the engine bay for fear of getting the ECU wet..
also someone mentioned somewhere there was the possibility of the oxygen/air sensor (?can't remember the correct name of it right now) being blocked/damaged and if that happens, automatic engine cut-off as a safety feature to the engine.. again, this is exposed to water in washing of the engine bay.. actually i've never heard of anyone washing the engine bay except here in Malaysia (well not in Manila and Melbourne anyway
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Hi Adrian, I wash the car myself. For the engine, so far I have only used wet cloth and a powerful vacuum cleaner to blow all the dust and sand away. However, the engine cut-off still happenned. I managed to file a complaint to SDHM on their web site last night. They called me this morning and was concern about the problem I had with the engine vibration and the cut-off. According to the service personnel, they need to update the software on the ECU. They have done that for many of their customers and so far no one came back complaining about the engine cutting off while the car was still moving. Isn't this a design fault? If it is a bug in their software, Hyundai should recall all their cars. I can't imagine travelling at 200km/h only to realize I lost power steering, engine power and worst still brakes. Shouldn't all of us owner of this Sonata make a stand and write to them at their web site? I am not sure the software update will really solve the problem or they are just hoping it will solve the problem.
In the end, I'm still quite upset about the engine vibration. Putting my hand on top of the engine (where the words DOHC is)while it is idle, I felt after about 5 sec, I was putting my hand on a massager as the hand started to feel weird akin to us using the actual vibration massager. All in all, for a 10 month old car, it diminishes the pleasure of driving this car whenever u come to a stop. SDHM has booked next Monday morning a special slot for me to bring the car in for inspection for the two problems. They said I will have to leave the car there for 3 days. Luckily they said I can have a spare car to use while they check my Sonata. I hope its true. As many of you have mentioned, you are also unhappy with this engine vibration as when time passes by, the engine gets older, the rubber mounts on the car will harden, and I can just guess the car will vibrate even more.
Hence, is there anything that Hyundai can do? I would love to compare the engine vibration to a brand new car, to see how much difference the vibration is. if the new car engine vibrates a little, than, I would suggest a caution for all current owners who just got their car, Dont rev your car engine beyong 3k RPM if you want to ensure you have little vibration, else you will end up like us, driving in a vibrator.
PS: The other day, a BMW 5 series parked beside my car, I was just standing beside it and it was amazing, how the engine sounded (hardly any noise except from a slight breezing sound coming from the fan) and when I touched the body of the car, NO VIBRATION at all. Amazing, but of course you will say how much the BMW cost. Hence try to compare the Sonata to a same aged Camry.....