# intentional ignition delay (in new Fords?) **URL:** \ **Category:** Factual Questions\ **Created:** [December 26, 2005, 7:44pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276 "2005-12-26T19:44:08Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Pasta](https://avatars.discourse-cdn.com/v4/letter/p/ecccb3/32.png) [@Pasta](https://boards.straightdope.com/u/Pasta)\ **Post date:** [December 26, 2005, 7:44pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/1 "2005-12-26T19:44:08Z")
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. So, what’s going on in that tenth of a second? ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [December 26, 2005, 8:03pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/2 "2005-12-26T20:03:13Z")
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. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [December 26, 2005, 9:51pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/3 "2005-12-26T21:51:53Z")
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? ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [December 26, 2005, 10:18pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/4 "2005-12-26T22:18:16Z")
> [@kanicbird](#): > > 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? I have never heard that in all my years of working on these systems. Sounds like an old wife’s tale to me. ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [December 26, 2005, 10:38pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/5 "2005-12-26T22:38:22Z")
> [@Rick](#): > > 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] 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?? ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [December 26, 2005, 10:53pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/6 "2005-12-26T22:53:05Z")
> [@Musicat](#): > > 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?? No we don’t need a computer we need 3 or 4 fucking computers on a high speed network. :eek: ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [December 26, 2005, 11:30pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/7 "2005-12-26T23:30:30Z")
> [@Rick](#): > > I have never heard that in all my years of working on these systems. Sounds like an old wife’s tale to me. Nope, on my Dodges, the system needs a split second to charge up the systems. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [December 26, 2005, 11:53pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/8 "2005-12-26T23:53:26Z")
> [@Rick](#): > > I have never heard that in all my years of working on these systems. Sounds like an old wife’s tale to me. 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. ---
**Author:** ![R.P.McMurphy](https://avatars.discourse-cdn.com/v4/letter/r/7993a0/32.png) [@R.P.McMurphy](https://boards.straightdope.com/u/R.P.McMurphy)\ **Post date:** [December 27, 2005, 12:07am UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/9 "2005-12-27T00:07:37Z")
> [@Musicat](#): > > 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?? Not if you owned a Chrysler on a cold day. You could count on spending at least 10 minutes and maybe a battery charge to get it going. ---
**Author:** ![Philster](https://avatars.discourse-cdn.com/v4/letter/p/13edae/32.png) [@Philster](https://boards.straightdope.com/u/Philster)\ **Post date:** [December 27, 2005, 1:33am UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/10 "2005-12-27T01:33:32Z")
> [@Musicat](#): > > 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?? 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. ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [December 27, 2005, 4:57am UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/11 "2005-12-27T04:57:56Z")
> [@kanicbird](#): > > 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. :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? ---
**Author:** ![ombre3](https://avatars.discourse-cdn.com/v4/letter/o/da6949/32.png) [@ombre3](https://boards.straightdope.com/u/ombre3)\ **Post date:** [December 27, 2005, 9:49pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/12 "2005-12-27T21:49:42Z")
> [@Spartydog](#): > > Not if you owned a Chrysler on a cold day. You could count on spending at least 10 minutes and maybe a battery charge to get it going. Depends on what year Chrysler product. 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. ---
**Author:** ![R.P.McMurphy](https://avatars.discourse-cdn.com/v4/letter/r/7993a0/32.png) [@R.P.McMurphy](https://boards.straightdope.com/u/R.P.McMurphy)\ **Post date:** [December 28, 2005, 1:22am UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/13 "2005-12-28T01:22:53Z")
> [@ombre3](#): > > Depends on what year Chrysler product. > > 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. ---
**Author:** ![enipla](https://avatars.discourse-cdn.com/v4/letter/e/54ee81/32.png) [@enipla](https://boards.straightdope.com/u/enipla)\ **Post date:** [December 28, 2005, 1:29am UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/14 "2005-12-28T01:29:18Z")
My '76 Chevy plow truck takes a bit of finnese with the choke on a cold day. My '93 Pathfinder, all electronic/injected has never failed to fire right over. I’m talking about -20 f. That’s about as cold as it gets here. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [December 28, 2005, 4:11am UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/15 "2005-12-28T04:11:57Z")
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. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [December 28, 2005, 2:02pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/16 "2005-12-28T14:02:06Z")
If that hampster takes a dump again I give up **Rick** I 1st heard of the pause in a newspaper Q and A ‘car talk’ type column, and have seen/heard it more then once. Here is something I dug up: > [@](#): > > Answer: This is not uncommon for fuel injected vehicles. By turning the key to “on” for a moment, before turning to “start”, you allow the fuel pump to pressurize the fuel lines before you start the engine. Quickly turning the key from “off” to “start” may not allow the fuel pump to build up enough pressure in the lines [http://www.loudoun-net.com/haines/villagerquest.htm](http://www.loudoun-net.com/haines/villagerquest.htm) ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [December 28, 2005, 11:02pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/17 "2005-12-28T23:02:42Z")
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 > [@](#): > > I’ve heard it recomemded that you pause between turning the key from ‘on’ to ‘start’ **to allow the computer** … 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. ---
**Author:** ![Pasta](https://avatars.discourse-cdn.com/v4/letter/p/ecccb3/32.png) [@Pasta](https://boards.straightdope.com/u/Pasta)\ **Post date:** [December 29, 2005, 7:11pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/18 "2005-12-29T19:11:50Z")
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 > [@](#): > > For the next 35 milliseconds nothing happens (the computers wait to see if any programming commands are coming, or if this is normal start). 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…) ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [December 29, 2005, 8:41pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/19 "2005-12-29T20:41:08Z")
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. ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [December 29, 2005, 10:45pm UTC](https://boards.straightdope.com/t/intentional-ignition-delay-in-new-fords/337276/20 "2005-12-29T22:45:37Z")
> [@Musicat](#): > > 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?? 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.)