Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Can an automatic transmission be bump start an engine

Christ · 10-03-2010, 01:13 PM

Ok, it won't kill your transmission, because you have no way to introduce torque from the wheels back into the transmission. Unless you have a fluid pump at the rear of your transmission, which you probably don't, it won't start your engine back up, either.

Essentially, unless you're pumping fluid, the transmission won't go back into gear at all, so you'll remain in neutral, until you start the engine back up and introduce fluid sufficient to fill the passages under pressure and engage the Drive gearset.

While it's not going to do anything for you, it's also not going to harm your transmission any more than coasting engine off in neutral actually would.

IOW - don't do it.

10-03-2010, 01:13 PM	#4 (permalink)
Christ Moderate your Moderation. Join Date: Nov 2008 Location: Troy, Pa. Posts: 8,919 Pasta - '96 Volkswagen Passat TDi 90 day: 45.22 mpg (US) Thanks: 1,369 Thanked 430 Times in 353 Posts	Ok, it won't kill your transmission, because you have no way to introduce torque from the wheels back into the transmission. Unless you have a fluid pump at the rear of your transmission, which you probably don't, it won't start your engine back up, either. Essentially, unless you're pumping fluid, the transmission won't go back into gear at all, so you'll remain in neutral, until you start the engine back up and introduce fluid sufficient to fill the passages under pressure and engage the Drive gearset. While it's not going to do anything for you, it's also not going to harm your transmission any more than coasting engine off in neutral actually would. IOW - don't do it. __________________ "¿ʞɐǝɹɟ ɐ ǝɹ,noʎ uǝɥʍ 'ʇı ʇ,usı 'ʎlǝuol s,ʇı"