If somebody tries to push start an automatic, what are the "bad" effects of this?

Question

The battery was flat..
The car was on a hill.
My wife tried to "push-start" it by letting the brake go....
She put the car into "P" while driving at 20mph, and then "D"
Ohhh dear..
What part(s) should ask the garage to look at/replace?
What is the worst case?

It appears to work ok at the moment despite the trauma.

Answer 1

You can`t push start an auto.
As long as park still stops the car from rolling,(put in park n` try and push) you shouldn`t have to fix anything.

Answer 2

Generally speaking you should never engage/disengage drive, reverse and/or park on an automatic if it is travelling over 5mph otherwise you can cause damage so severe it will result in the automatic gearbox being written off.

All auto box manufacturers state that you should never push start a vehicle with an autobox as the clutch bands will be damaged as they are not meant to drive the engine at all.

I would recommend telling the garage exactly what has been done so they can plug the car into a OBD diagnostic kit and locate faults on the box. If the box does need replacing you could be talking about a repair bill over a thousand pounds.

Answer 3

If put into Park whilst moving there will be a horrible sound as the park pawl tries to locate in the transmission. Most likely the movement will keep pinging it back out but severe wear will happen. If Park no longer stops the vehicle from moving the pawl will have sheared off (costly).
It's highly unlikely bump starting an automatic will ever work.

Answer 4

The bad effects are: first your likely to have an heart attack trying to push start, secondly auto matics wont jump start as you dont have a drive connection until the engine is running,
you will have no doupt damaged the parking pawl by selecting "p" while it was in motion. it'snot the end of the world, you might be lucky that any broken parts could have droppedto bottom of the gearbox and stuck to the debris magnet.. get your battery checked and renew if required..

Answer 5

On older auto boxes fitted with a neutral position as opposed to park, it was common knowledge that you tow it in 'N' to 10 mph and then engage 'D' to bump start it. But you should not attempt to tow it from standstill with any gear selected. I see no reason why it still doesn't apply. If you have broken the parking pawl on your box, make sure you change the oil immediately, and check the drain can for the missing parts. Leaving them in the box, is like pulling the pin out of a grenade, it will, if you wait long enough blow the box up.

Answer 6

You cannot push start an automatic. Now putting it in park is really not a good idea while moving, and for a short distance drive will not hurt it. (Heard a clicking noise when in park I bet) If you want for your own peace of mind take it to a transmission shop, but if it is running fine no most likely no real damage done, just keep an ear out for anything that sounds, or behaves funny.

Answer 7

Stripped the locking pawl at the very least when the car went into park. You cannot start an auto by pushing it.

Answer 8

I don't think you can push start an automatic, only a manual vehicle. Your transmission gears or the small balls that direct the fluid in the transmission can get damaged.

Answer 9

if its working fine now dont worry about it, it might have damaged the internal part that holds it on a hill in park but if thats still working you might have got lucky , I'll bet she wont try that again

Answer 10

you get very hot an sweaty bcoz it will not start that way


you could damage the internals if you tow it bcoz there is still oil pressure there, and needs the engine driving it to get pressure in right place rather than wheels driving it