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Stupid useless Eco Stop/Start "feature" in newer cars!

I recently bought a 2015 Mercedes Benz S550. I love the car, but I hate - no, make that despise - the idiotic Eco Stop/Start function that turns the car off when idling or parked for a few seconds. It enrages me! There is NO WAY that the miniscule gas savings makes up for the constant wear and tear on the starter, ignition system and engine! Whoever the moron is that conceived of this should be tied to the bumper and dragged down the 405 freeway during rush hour. 'Nuff said.


Try reading the thing called the vehicle manual and it should show how to turn the start stop function off. Unless I am mistaken it only works in the E-mode.

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…which also leads to the question of why somebody would buy a vehicle (or any other product, for that matter) that has a major design feature that he/she doesn’t like. To me, this sounds like a case of someone who failed to properly research all of the features of his/her potential purchase prior to buying it.


My wife and I rented a Jeep that had this feature. We were able to turn it off, but had to do so each time we restarted the vehicle. As a mechanic, it made my heart skip a beat at every red light til I got somewhat used to it- i was constantly thinking the silly thing was stalling on me.

Now that we are in the market for an SUV type vehicle, we know not to look at Jeep if we don’t want that as a feature…

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We test drove a car with that feature, not a deal breaker, other issues were, One hopes things are engineered to provide longtime dependability, though I have turned into the lease it and don’t worry about it category for the wifes car, my car, drive it till it dies, revive it and drive it some more.

I rented a Chevy Cruze a couple years ago and found it had that feature. It was so subtle I doubt most people would be aware of it, except for the quiet and vibration-free idle. There was no thump or bump when pushing the accelerator, just a very satisfying amount of torque and acceleration. Long-term durability remains to be seen, but I would think it has a more substantial starter motor than the traditional ones. Anyone know?

Gotta agree and don’t want it, but it’s not necessarily something you would ask about or check into before buying a car. Maybe now yeah.


We rented a BMW X3 with this feature. Turned it off immediately- and unfortunately - every time we started the car. There may have been a way to turn it off permanently but we didn’t want to waste the time figuring it out.

Rant from the OP aside. It does save gas and THAT is the primary concern of this feature - nothing else.

It’s a lot more convenient than having to manually switch off the engine and then manually restarting at every stop.
I once milked 56 mpg out of a Kawasaki ZRX1200 by hitting the kill switch and holding in the clutch whenever the engine wasn’t needed. Don’t underestimate the idle fuel consumption of a gasoline engine.
Normally ridden, this motorcycle gets around 45 mpg.


But, wouldn’t a test drive have revealed this hated feature to the OP? Even a relatively brief test drive would have to include a few stop lights or other situations where the stop-start feature would rear its intrusive head.

Did the OP buy this expensive used car without test driving it?

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From what I have read the start/stop feature only works in Eco mode and can be turned off after car is started.
Simple solution: back out of garage-fasten seat belt while garage door closes-set temp control-turn on cruise control-push button to turn off start/stop-drive on and find something else to drive yourself crazy.

I had an F150 crew cab as a rental a couple of weeks ago for 6 days. It had auto off/on and I got used to it after a while. Turn off was barely perceptible, and I really didn’t notice it until I recognized the truck restarting. Maybe the truck is so big that the stop/start cycle is damped out. IIRC, the engine would not turn off at stops if it was in sport mode. Sport mode in an F150? Really? Speaking of rentals, sometimes there is an owner’s manual and sometimes there isn’t. This truck did have one, but auto stop/start wasn’t annoying enough to send me looking for a remedy.

The ECO Start/Stop mode is also only activated when the transmission is in E-mode. The button to control this function is located on the console next to the COMAND controller. E-mode and consequently ECO Start/Stop is automatically turned on every time you start your Mercedes-Benz and will need to be deactivated each time should you prefer.

you bought a S550. you are a cake eater. you are allowed to despise things.
its all about gas mileage now. there is a reason your S class does not have a turbo 4 cyl motor
you have a nice newer luxury car with no problems. you have an annoyance. learn to live with it.

If you like the car otherwise, i wouldn’t let this feature ruin it. I’d make a little electronic circuit to automatically defeat it everytime you start the car. Maybe you know someone who has some electronics skills and they could help? Super easy little timer chip and a relay wired across the existing switch if it’s mechanical or logic output or whatever…

I didn’t like the VCM feature of my van. Did some research found out the computer will not enable that feature unless engine is fully up to temp. So made a circuit that goes between the temp sensor and the computer. It keeps the input reading a few degrees lower than actual. Just enough to defeat VCM but not interfere with emissions or other engine function. No more annoying vibration at a cost of 1-2 mpg.

Why put up with annoyances, eliminate them instead :wink:

If you’re on a test drive and the motor cuts off at every stoplight, you might just ask why. :wink:


I plead guilty to not researching the car well enough… stupid me, I didn’t realize that people buy S550’s because they get such great gas mileage! Seriously, this is the newest car I’ve bought in a long time, and I bought it for comfort and performance. I don’t drive a lot, maybe 5-6,000 miles a year and so I don’t care about the gas mileage. I’m 65 and have been driving since I was 15. I’ve never even heard of this “feature” (more accurately called an aggravation). Now I know, and will turn Economy to Sport and solve that problem. Thanks for nothing, Mercedes!

If I were a dealer aware of the dislike for this feature, then I’d disable it for all the vehicles that were to be used for test drives. Why risk having some of your customers walk away just from a test drive?

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Anyone else like me in wondering whether the starters in these cars are the same as MB cars without the stop/start feature?

With all the extra stops/starts, the expectation is that the starters will need replacing sooner, but likely after the warranty runs out.

And here’s an MB discussion that doesn’t suggest the expectation is wrong:

If you are buying a new car, you won’t be trying that particular car out before you buy it. So you need to know if the demo car has the same features as the car you are buying.

A lot of the new cars that have the automatic stop and start feature are actually mild hybrids and don’t use a traditional flywheel ring gear starter. The 2018 S550 uses a starter/alternator that’s between the engine and transmission and in addition to starting the engine, can add 21 horsepower to the engine for passing power, when it’s not helping the engine, it’s an alternator that recharges the 48 volt battery.
People who have driven this car claim that it is so seamless that you may not even realize the engine is shutting off at stops. Being direct drive and brushless, there’s no reason the starter/alternator shouldn’t last as long as the rest of the car. It will likely outlast a conventional starter in a conventional car.
A motor/alternator that can provide 21 extra horsepower for passing can also sink 21 horsepower for extra engine braking while charging up the battery providing some kinetic energy recovery during braking.