So I took a 500km trip from Vancouver to Vernon BC yesterday with my ml350 and since I always take this trip once a month using rental cars I kinda know exactly where to get gas without being stranded on the mountains. There is a 150km stretch that I know you wont find a gas station or even a house along the highway. So for the first time I decided to use my own car for the trip to pumper myself and to see how well the ml350 will do on the mountains in full load. I drove the car with only 1/3 tank full and was planning to stop on Hope BC for gas and somehow "I forgot" because of how comfortable the ride was with matching nursery songs in the background. I only found out the car was on its final liters of gas when the car displayed low fuel. Now when I saw this warning I was half way to that 150 km no gas station zone. So I kinda asked myself what to do as I know I wont reach the next gas station. I quietly turned off the AC and just let the fan run to somehow save a few drop of gas. I was thinking of calling MB roadside assistance to tell them to wait for me somewhere along the way and tell the other-half about the screw-up I just did. I know if I tell her that we might pull over along the highway and what the problem was there will be a huge fight and I dont want that to happen YET. So I run a few scenarios on my head on what exactly might happen.

1. Tell her now and accept the full on rampage and the entire weekend is over then just call MB assistance and ask for gas.
2. Call MB assistance and tell them to have someone wait on a designated area as I have car problems but never mention anything then pull over and open the hood and while outside tell them to have gas with them and tell the wife I dont know what is wrong and just keep driving until the car dies down. Still wife will be pissed and might ever get a MB again.

I told myself to go with #2 and act it out and have the wife be half pissed on me and half pissed with MB. Then I saw something I did not ever want to see. A red icon telling me to I dont have any gas anymore then the gas needle was literally pointing South. This happened when I still have 100km to travel then I saw a sign on the side of the highway "runaway truck ramp" then it hit me, what if I coast in nuetral all the way down to the town and only gas up when the speed dips down to 100 to maintain the highway speed? I know it is dangerous and the car might behave differently when I need to do a emergency manuever but I dont see anyone in front and at the back so I decidedvto do it and slipped the lever to nuetral. The ML coasted at a steady 120km/hr and the rpm dropped down to 750. When I first flipped back the transmission to D was waiting for a sudden jerk but nothing happened and proceed to hit the gas to keep the speed while on uphill and while exiting. In total I did flipped back to drive total of 4 times max of 1 minute each. With my amazement I did reach the first gas station in Kelowna and happy to retain my manhood. Now I am worried about the ML and hopefully I did not break anything.

Next time I am taking the rental and not risk this happening again or just not be stubborn. I am amazed though that 1/3 of gas manage to reach 400 kilometers even though I cheated.

So what do you think? Did I break anything? I know what I did was stupid so dont bash me with the stunt I did.

 

Probably no damage, but you actually wasted fuel. Modern computer controlled cars have something called DFCO - deceleration fuel cut off. When you take your foot off the gas, the computer completely shuts off fuel to the engine. The kinetic energy of the rolling car is transferred back up through the wheels and transmission to keep the engine spinning, so you have power steering, brakes, ac, etc. so you cover all that distance burning no fuel at all, not even the amount required to idle the engine. You can really see the effect of DFCO by bringing up the "from start" fuel economy display. Take your foot off the throttle early to coast towards a distant red light, and you will see the fuel economy jump as you cover that distance while using no gas.