Does this Car Push/Roll Start?
 

In the event of the battery being too low to start normally, can I start this car with a push/roll? Or do the modern ignition and fuel systems require me to use jumper cables?

If it's manual and the ignition is in the on position you can push start it like any other manual car with a dead battery. The ecu tune does the same process as it would do when the starter kicks over fuel injection or not.

But it's no substitute for not having jumper cables in your car to help a friend or something, you can practice it a bit if your bored honestly up a hill or down a incline in reverse or 1st I used to do it when I had a manual corolla, but don't keep doing it repeatedly for no reason.

What about cars with keyless entry/push start?

I've bump started my car before. Same experience as doing it to a car from the 60s, the only difference is that this car WREAKS of gas for about 5 min afterwards.

yes works fine


push start button twice without depressing clutch to turn ignition full on.


Then clutch in push car select a gear and let clutch out.




with all modern cars though you need enough power in battery to run the ecu and ignition/injectors for a push start, so if battery is completely dead theirs no chance. Only works if battery just not strong enough to turn starter motor

You would have to be rolling when you pushed the button and there would have to be enough charge left in the battery for the circuit to sense the fob and know you pushed the button. It may work but would be very tricky and I don't think it would be a good idea to try it.


Edit: Not fast enough again. What Steve said^^^

He is right on, there has to be enough of a charge to fire the coil packs. Unlike the cars of old the push will not spin the alternator fast enough to charge the ignition system. It takes a lot more to spin the starter, as you will notice every thing going dim. Starting in second gear is also easier as you are not turning engine over as fast. Lastly, if you use a toe strap you can charge a dead system but be aware the car will jump forward when it starts so use a longer tow strap.

I read somewhere (including manuals of FRS and of other cars) that with pushstarts there is a danger of overheating/fire of the catalytic converter. I it's about unburnt fuel getting there before the engine starts running. No idea though how real the danger is.

Doubtful, there are many other situation where with a tune where unburnt fuel enters the exhaust stream when the engine is essentially off throttle.

Not to mention that if you have raw fuel in that quantity pouring into your cats then the engine is going to be so badly flooded that it will not start anyway. Without starting there is no heat to ignite the fuel.

Not sure but doubt it would burn even if running though since the exhaust gases would likely deplete the oxygen to below the level required for combustion. Could be wrong on that though since I have no idea what the oxygen level in exhaust gases may be.

Best I don't let my battery die then! :-)

Without researching it any more, I'd theorize the following scenario.

During Several unsuccessful attempts at push-start the air-fuel mixture flows through the engine and fuel is collected in cold cat. When the engine ultimately starts, the cat heats up, and suddenly you have a significant amount of fuel in the presence of very hot catalysts, and things get nasty.

One thing that my brilliant theory does not explain, is why things would be any different if a few unsuccessful starts using the starter are followed by successful start.

meh

Nope No fires in the exhaust of a running car. Just as I thought there is just not enough oxygen to burn the fuel. Now if you don't evaporate it all and shut it down allowing the oxygen to enter the system...


https://www.ngk.de/uploads/tx_templa...motoren_en.jpg

That literally is not how it works, the cat stays cold it takes quite some time for it to warm up, so much so any unburnt fuel will ignite in the exhaust regardless by that time or just get sent into the atmosphere, if it does nothing dangerous will happen it's contained. People are actively creating tunes to do this by retarding ignition timing off throttle to get there exhausts to crackle and pop.

I like the bearings to have a supply of oil before loading the crank with the drivetrain.

I will not jump or be jumped on any car with a computer.

Charging a disconnected battery or just purchase a new one if it has issues, is the preferred route for me. Bad batteries kill alternators. Bad alternators kill batteries.

There is a sticker on your window for a number to call if you have a dead battery. Most manufactures do this for free.

There's a shred of truth to this but you haven't supported any of your wide swath of assertions. If you care to explain your reasoning, I promise I'll be civil with my responses.

Yes you can. Regardless of all the overcomplicatation put forth is this discussion.

Just turn the key on, put the gearshift into 2nd, engage the clutch, get rolling to a reasonable speed, disengage the clutch, and the engine will start.

Unless you have an automatic transmission or a "push to start" miracle of modern technology.

Then WHY?

You cannot push-start a modern car if the battery is fully discharged.

If it is fully discharged, you have no power to the ECU, no powerto the the FP, no power to the injectors, and no power for ignition.

All of those systems/devices are required to start the engine.

Ultra...

Say your voltage regulator is bad and puts out 17volts, it won't take long for the electrolyte to gas off or heat up the battery to the point of swelling, ect.

In the other scenario, assume you have a dead cell or a cell low on electrolyte. Your voltage regulator will keep allowing higher and higher amounts of exciter current to try to get the lame battery up to voltage...which never happens because of the dead or weak cell.

When one downshifts in a not so smooth fashion, these little springs are being pushed instead of being pulled.

I equate that to roll starting where the clutch is the driving force instead of what is being driven.

There is a sticker on your window for a number to call if you have a dead battery. Most manufactures do this for free.


Roadside assistance? This is not free, AAA in my case requires a yearly renewal of subscription fees.....

Bad batteries kill alternators. Bad alternators kill batteries.


Second part is true first part isn't always true, if you jump the car incorrectly you can totally destroy an alternator though. If there is a dead cell in the battery, it will though cause extra heat in the alternator lessening it's life cycle. As long as you replace it quickly enough that it doesn't keep trying to overcharge that dead cell you're fine. If you do something stupid like leave the lights on a car with a new battery you're for the most part fine....

I like the bearings to have a supply of oil before loading the crank with the drivetrain

What? Turning the engine over is a heavy load as well, and if anything a load has to be applied to get the oil pump to start moving oil to the valvetrain and bearings....

This is an important assertion, it will only work if you have enough power for maybe when all the ignition lights and internal lights to appear dim

If you quote me I'll know you responded.

First part is true. Second part is true only in the case of a shorted cell. Not a common failure mode. My first gen Eclipse sucked at dealing with a deeply discharged battery. Regulator would take a dump every time. I finally modified my fourth alternator. Replaced the internal regulator with an external one from a Ford F150.

That's not going to hurt anything. They can handle it. Don't forget what's on the other side of the friction disc. It's the flywheel.

I'll hold off on the oil thing for now. ;)

You can definitely do it. Had to do it to my 86 last week after not being started for 2 months. Started it with a jump starter then drove somewhere. I sat in my car while dad went to the shops, had the radio going for 5 minutes and battery went flat. Got out, pushed, jumped in, pop clutch with ignition on and with a bit of jumping, boom she came into life.

It would be interesting to know what is the rationale behind owner manuals discouraging push-starts.

I'm going to guess concerns of personal injury or property damage due to loss of control of the vehicle.

That and if you screw up too bad you can fuck the car up big time!

Well, yeah but you can do that just driving it.

Owner's manual should probably discourage that as well. :D

The point was they don't want you to blame them for screwing it up by push starting it. CYA on their part.

Oh, I know. Just yanking your chain. :cheers:

Pretty sure the manual says no chains as well actually.

Lololol.... spit my coffee. You win.

wait, can I push/bump start my car in reverse?

Yeah, but in other cases they just say that. E.g., "Do not adjust the position of the steering wheel, the seat, or the inside or outside rear view mirrors while driving. Doing so may result in a loss of vehicle control that can cause accidents, resulting in death or serious injury."


They could say the same for push-starts, but the say
"Do not pull- or push-start the vehicle as the three-way catalytic onverter may overheat and become a fire hazard"

I think you are confused about the nature of catalytic converter fires. The fires are not in the converters but caused by unburned fuel heating up the convertor and igniting materials outside of the convertor not inside it.
Here:
http://www.tceq.state.tx.us/airquali...h/catfire.html


I can not find one single reference to fires in the convertors anyplace but if you have a link I would like to read about it (it has sparked my curiosity if even possible)


And if I am not mistaken the manual actually does reference not parking where the convertor could ignite materials.

Exactly this, liability, they don't want to be responsible in any way for suggesting that moving the car without steering or engine power is a safe way to start the car with little risk.

I was able to do it on my corolla :lol: the engine spins the same direction regardless, but you have to be careful the jerk when the engine kicks in is slightly worse in reverse.

Haha. Funny story I had to do this 2 weeks ago when my car wouldn't start . when my friend was taking pics of my car in a parking garage. Luckily I was facing down so I just threw it into first, popped the clutch and hit the start and it started first try. The pics were worth it.

Another funny story. I knew my battery was getting bad, but I was turning the car in (lease). That battery had finally died after 3 long years in the Arizona heat. Anyway ... the pre-turn lease inspection guy comes over to the house.

He turns on every item ... checking all the stuff without the car running. I'm thinking that when he finally goes to start it .... it probably won't start. He goes to start it .... and it "barely" starts. He didn't say a thing. I passed the inspection.

Here's the funny part. Drove it to the dealership to turn it in. Got my paperwork and watched as the attendants had to push start the car to start it.