I often find myself in rental cars, and when I do, it’s usually whatever random car they happen to have on the lot. Included among my recent cars are:
2005(?) Ford Mustang
2005(?) Ford Freestar
In both of these cars, when I turn the key to “start”, there is a fraction-of-a-second delay (maybe one-tenth of a second) before anything happens. It would not be noticeable to a passenger, probably. It’s just that after years of key-turning/engine-cranking, one gets used to the rhythm of the procedure.
I first noticed it in the Mustang (where the delay was a bit longer), and I thought it might be an attempt to add to the “power” image of the car. (That is, the delay reminded me of the movie trick of always having a delay between the “click” of the button and the corresponding huge explosion / rocket launch / trap door opening.) But when I got in the Freestar (a minivan), I threw that theory out the window.
Not sure about Fords in particular, but on Volvos here is what goes on when you put the key in:
[ul]
[li]The central electrical module commands the antenna ring around the keyhole to interrogate the chip in the ignition key[/li][li]The central electrical module powers up all the other computer nodes in the car (18-22 depending on how the car is equipped)[/li][li]For the next 35 milliseconds nothing happens (the computers wait to see if any programming commands are coming, or if this is normal start)[/li][li]The central electrical module verifies that the key in the ignition is in fact authorized[/li][li]The central electrical module sends a password to the engine control module (The duck walks at midnight)[/li][li]The engine control module verifies that the central electrical module sent the correct password, and then returns his password (It might rain on Tuesday)[/li][li]The central electrical module verifies that it got the correct password back[/li][li]The central electrical module verifies that the car is either in Park or Neutral[/li][li]The central electrical module energizes the starter relay (the car now starts cranking)[/li][li]Once the engine control module sees engine RPM >40 a request is sent for fuel pump activation[/li][li]Pump electronic module starts the fuel pumps (car starts)[/li][/ul]
Bottom line there is a whole lot of stuff that goes on behind the scenes. I wish my PC booted this fast.
I’ve heard it recomemded that you pause between turning the key from ‘on’ to ‘start’ to allow the computer and everything to fully come up. Perhaps Ford is just compensating for poor driver habits?
Jeez. Remember the days when turning the key completed the circuit to the starter motor which cranked the engine and it came to life instantly? Now we need a fucking computer to start it??
Nope it was not a old wife’s tale, perhaps a new wife’s tale as it was OK for non-computerized/ carberated cars to just start it up, when FI and these computers came about the pause was recomended.
Yes, if you would like improved fuel economy, reduced emissions and a safer automobile, you need computer power. Even if fossil fuels/int cobm engines were abandoned, the use of computers in cars would likely be even more extensive.
:dubious: Like I said before I have never seen that recommendation in any owners manual, repair manual, service manual or any other authoritative source. We’re in GQ here looking for factual answers. So you got a cite for that?
My old 1939 Plymouth Coupe back in the 60’s when I was in college would seriously outperform modern day cars in cold weather starting.
I would pull out the choke in SERIOUSLY cold weather. Crank it. 2 seconds later it started right up. Pushed the choke halfway in------and I was GONE. Choke pushed all the way in after about 3 minutes. Could drive all day long.
All the time that the “modern” cars around me were cranking and cranking and hoping on a bet and prayer the engine would fire and start up.
They tended to make fun of my 39 Plymouth Coupe. “How dare you have that piece of old crapola in this neighborhood?”
But they never made fun on cold winter mornings.
And I would laugh my ass off----toodling off in the distance while everyone else was just sitting there--------cranking and cranking and cranking.
The '39 is a little before my time. The Chryslers of the '50, '60’s and '70’s (before electronic fuel injection) had a reputation of being notoriously hard to start in cold weather. It probably had something to do with the “automatic” choke. Note that you said the '39 had a manual choke (same as a lawnmower or snowblower that needs to start on demand).
Anyway, thank whoever for electronic fuel injection, electronic ignition and computers. I’ll tolerate the 1/10 second delay compared to what used to happen in the days of carburators and mechanical ignition.
If you want to put it in perspective, keep in mind that the average car these days has significantly more computing power than the spacecraft that took the astronauts to the moon. People just take it for granted that when you turn the key it goes.
Ok, your cite is from some guy that owns a car, not zactly an the best cite in the world. Also what I was questioning in your first post was
You “cite” talks about allowing the fuel pressure to build before cranking. While building fuel pressure does come under “everything to come up”, allowing th fuel pressure to build is NOT allowing the computer time to boot up. While this may seem like a nit to pick you have to realize that computers in cars don’t require long boot up times like your PC. Also the OP talks bout a .1 second delay. How much fuel pressure would you build up in a tenth of a second? Not much is the answer.
My personal opinion of this guy’s suggestion is that he has a car with a rest pressure problem (leaky injector, leaky check valve are the two most likely suspects) and rather than fixing the problem, he has developed a work around.
Thanks for the responses. Rick’s original reply is the sort of answer I was looking for. This is certainly a computer delay, and I was looking for what the computer was doing in that time, like
While cars certainly do have electronic systems all over, the networked HAL9000-esque computer cluster bonanza seemed like something that would show up on higher end cars only. I guess everybody’s doing it that way these days, then?
(And I’m sure they know what they’re doing, but I want the doors to lock and unlock when I want them to. But that’s a post for another forum…)
FWIW the new Freestar uses the Volvo electrical design. So what I described in my post is most likely exactly what happens when you go to start one.
While networks did start with high end cars, all new cars now have a network at least with the powertrain.
Yeah and my father (b. 1906) used to tell me that whenever he drove the 60 miles to Atlantic City he would take (and expect to use) a screwdriver and pair of pliers because there wasn’t anything on the car he couldn’t fix with them. He also made sure he had at least two spare tires. (He must have also had a jack and a tire iron, but somehow they didn’t get mentioned.)