Instantaneous starting on newer cars

[spasm3]

Originally Posted By: SteveSRT8
Originally Posted By: meep
remember the pre-injected days? A warb carb'ed motor could indeed crank over on one hit-- just bump it. The distributor knew where it was...

or could deplete the battery on a cold wet day, and never get (there)


Nothing could bring out the joy of a points/distributor setup like a cold wet day! That would expose the poor parts immediately...


Yep , if it was wet and stopped starting well, grab the wd-40 until you get a new cap an rotor.

 

[artificialist]

If the EFI system needed both cam and crank sensors, a minimum number of revolutions would be needed before the computer could even fire the first spark. That kind of system is a must on sequential EFI and GDI. However, some engines either fired all injectors simultaneously, and the moment the distributor reached the next cylinder, the ignition coil could start sparking, and there would be fuel in each cylinder.

I remember my grandmother had a 1993 Buick Roadmaster with a GM TBI engine. I put an ACCEL ignition coil in it, and the sparks were so hot, it took about 1/3 as long to get the engine started versus the OEM coil.

I have been told this also works if you have a carb engine with an upgraded electronic ignition. You do have to set the choke and accelerator absolutely perfect, however.

 

[hattaresguy]

Because of stop start technology engines have to start up faster. A lot of them stop in a certain position, ie a specific cylinder at TDC for example to aid in quick starts.

 

[hattaresguy]

Originally Posted By: JHZR2
Originally Posted By: eljefino
IIRC the Ford Modular was one of the first engines/ control systems that mandated a certain number of cranks (4?) before starting was allowed to happen. Before then, the computer would be trying to run at every crank trigger event.




Interesting. I always wondered if this was the case. My chevy truck will catch before the first cylinder is fired it seems, yet my 91 BMW gets exactly four cylinders (the cyclic cranking noise, whatever it is actually) and then catches on the fifth without fail. The DI BMW needs two and a half every single time.

I was never sure if the computer wanted to see the engine turning or if it was something else.

I kind of like the idea of the engine moving a bit without fuel injectors pulsing, just to get fluids moving, then fire...


On older Mercedes and I bet your 1 series the ignition is just a switch. You could probably just hit the start button fast and release it and the computer would take the motor threw the starting procedure, ie crank it until it fires.

On older E class most people don't realize this and treat the fob like a key, holding it to crank. When in reality your just sending the ECU a start command and the starter will crank and start the engine regardless of if your holding the key in the start position or not. You can just do a quick wrist flick to the start position and let go. On the diesel ones if I remember correctly it will even attempt a second start if the first attempt fails. Look mom no hands!

 

[MCompact]

I have a Delta Mark 10B CDI on the 1975, which helps a bit...

 

[jrustles]

My car don't prime the fuel pump until the key is bumped to start. Cranks longer with low fuel, otherwise 2 maybe 3 compression hits before it fires. If the line is primed however, it fires nearly instantly.

 

[dailydriver]

Originally Posted By: supton
Good chance the crank and cam sensors may have to see some edges on the (what do you call them? the things they sense--not the crank/cam but the gear-like object)


Notches on the reluctor wheel is the term I'm guessing you are looking for?

 

[antiqueshell]

Originally Posted By: Vikas
People who are talking about 2 second crank time; that is a L O N G time!!


No it really isn't, depending on the computer controls involved, it may likely be a result of improving emissions. For example the car may wait until the O2 sensor heating elements are already activated and heating.

Many modern cars will crank until around the 2 second mark, and it is completely normal.

 

[supton]

Originally Posted By: dailydriver
Originally Posted By: supton
Good chance the crank and cam sensors may have to see some edges on the (what do you call them? the things they sense--not the crank/cam but the gear-like object)


Notches on the reluctor wheel is the term I'm guessing you are looking for?


Could be. I always thought that was the term for the item in the distributor for ignition timing. Not sure what it's called when it's on the crank/cam, although it does do the same thing (provide rotational and positional data to the ECU).

 

[Jarlaxle]

Originally Posted By: meep
remember the pre-injected days? A warb carb'ed motor could indeed crank over on one hit-- just bump it. The distributor knew where it was...

or could deplete the battery on a cold wet day, and never get (there)


My friends k20 pickup, with s Road Demon carb on a ZZZ 350 fired right up at 5 below Monday! Pump it once to set the choke, then crank and fire.