True, but when the engine dies, you’re now fighting the hydraulics of the non-functioning pump and box so it will get relatively harder to steer under all conditions. So, for example, if the engine dies while you’re going 50mph, it will get harder to steer than if the pump was functioning. I ran one car for years with power steering disabled and even when cruising at higher speeds, the lack of power steering was noticeable. I think that’s what the prior poster felt and was conveying in their description. Something was definitely wrong with the Tahoe, like a stuck IAC or something causing it to stall in neutral…
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If your truck engine dies whenever you shift to neutral, moving or sitting still, that’s a malfunction, not a feature. The fuel shutoff I describe is a programmed feature.
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The original question, which was never answered by the way, was does it hurt the transmission to coast in neutral. Most automatic (and manuals too for that matter) have the oil pump on the input shaft. If the engine is running, it won’t hurt the transmission. If the engine is shut off during this coasting (scary scenarios ensue), then it will damage the transmission.
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My manual transmission Corolla definitely turns off the injectors when coasting in gear. I feel this happening on most every drive. Say I’m going down the road at 40 mph in 4th and the traffic light changes to red ahead. I’ll shift to 3rd and coast in gear as I slow down anticipating to stop for the traffic light. Once I slow to about 10 mph and still in third gear there’s a slight but noticeable surge forward as the injectors are turned back on. The computer must have some kind of algorithm it uses that turns the injectors back on before the engine can stall.
It’s pretty simple. Fuel comes back on when engine speed drops to 1000-1500 rpm.
My 1985 Accord SEi (first fuel injected Honda model in US) did this too.
seems like a dumb idea to me.
It saves a little gas I suppose. No fuel use at all while coasting in gear. So there’s that. This fuel off/fuel on transition can cause a jerking sensation however if the fuel injectors are a little clogged.
the engine still runs and wanting gas.
The ECU in most modern (90s and newer) cars will completely cut fuel if the RPMs are over a certain threshold when throttle position reads below say 3% for example. I have an exhaust cutout in my Turbo car for track days and when it cuts fuel you can clearly hear a difference in exhaust tone when you let off at higher RPM. As the RPMs drop below 1000 or so you can hear it adding fuel to prevent it from stalling. The youtube channel engineering explained has a great video explaining this (I am not affiliated with nor promote them whatsoever). As for transmission damage yes and no. It will cause unnecessary wear on your transmissions internals thus leading to its untimely demise. To negate this there is always rev matching when you reengage the drive gear similar to how you would drive a manual when engaging a gear to prevent jerking. None of this takes away from the fact that in many jurisdictions it is illegal to take the car out of gear when moving without reason other than it being required for vehicle operation such as a manual transmission or in case of an emergency if for whatever your transmission or drive train locks up and doing so would allow you to maintain more control of the vehicle. If you are involved in an accident as a result of coasting in neutral you will likely beheld responsible and ticketed accordingly if it can be proven that you where in fact doing so.
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Agree with @kravenscroft1316_165014. With a modern car the fuel savings are negligible.
While I get @meaneyedcatz’s points, his/her last point ignores the car adjusting fuel supply. It may seem like you are using less gas because you have to press the accelerator slightly, but in reality that ends up being about the same amount of gas as the car would use when idling.
Not to mention all the other possible repercussions you might incur, such as what happened in the car crash in The World According to Garp. 