Why the 90 has the brake in the start circuit

[TbirdSCFan]

Bit of a long story, but I think I figured it out.. Today my car wouldn't start.. I'm at home; times running short, so I jump in my wifes van, and run our daughter to school. Then I swing back by the house and have a few minutes to see what I can do before giving in and taking the van to work instead. Instead of figuring out the problem, I turned the key on, got out, took a wire and jumpered the starter relay to start the engine, then hopped in and left.

OK, so more laborious explanation.. I leave from the office, and the car starts just fine :confused: I get home and tell my wife about it.. she makes the comment "sometimes I have problems starting the van.. especially when its cold" She's the wife, so I tactfully ask "You aren't pressing the gas pedal when you try to start the van, are you??" :rolleyes: She responds "well sometimes.." :rolleyes: :rolleyes: "Honey, its a fuel injected engine.. you shouldn't ever press the gas pedal when trying to start it.. it has a computer and it'll get confused..."

I myself, of course, never have any problem starting the van.
Then it dawns on me.. The 90 year model requires you to hold the brake down to start the engine. The average owner can't easily push the gas pedal when his/her foot's on the brake.
So there's my theory.. they did it to keep people from mashing the gas pedal in the morning and screwing up the EEC's fuel settings. :cool:

[SC UL8R1990]

interesting point but i dont remember ever having to press the brake to start a car. However i do remember having to press the brake in for an automatic tranny.

Was this only in certain cars? (having to press brake to start engine)

[Parker Dean]

Originally posted by TbirdSCFan
So there's my theory.. they did it to keep people from mashing the gas pedal in the morning and screwing up the EEC's fuel settings. :cool: [/B]

Actually the Audi unintended acceleration issue was hot at that time. IMO, this was Ford's initial quick-fix before they could get the brake-shifter interlock engineered and introduced.

Despite the fearmongers (60 Minutes) assertions of defective cars, the engineers knew what caused unintended acceleration was mistaking the gas pedal for the brake in acar you're unfamiliar with. So the quick-n-dirty way to assure the foot is on the brake is to make you start the car with your foot on the brake. The MN12 does have the brake and accelerator pedals shifted slightly left when compared to other cars too. This makes it very easy to get the unintended acceleration. I know, I've done it way back when the cars were new. The MN12's are the only car I've ever done that to and I used to be a tech in a general shop so I've driven hundreds, if not thousands, of cars of all makes. Now that I own one I wouldn't make that mistake but the problem with the unintended accel situation was always with people who were borrowing, renting, or new owners of the vehicles.

Later, the brake-shifter interlock came about and the brake-starter interlock was dropped.

[MIKE 38sc]

Yeah Dateline did a segment on this issue a couple of years ago.
They talked several owners of the suspected so called sudden acceleration cars into letting them install small cameras in the re vehicals in the hopes they would catch it in the act, well they caught it alright.
I never will forget this lady who thought she was hitting the brakes trying to stop as another woman walked across a mall parking lot. She pushed gently on the gas pedal like you would when you brake but instead the car sped up. She started screaming OMG the BRAKES and this time she STOMPED what she thought was the brakes to the floor and held them! Only problem was it was'nt the brake pedal she was hitting, it was the accelerator. Luckily before she ran the woman down you could see she caught what she was doing because she corrected it quick and got stopped. She was either extremely shook up and really did'nt realize what she was doing or she did know she made a mistake but would'nt admit to it.
She maintained that she was hitting the brakes even though the camera footage showed exactly what and where her foot was at all times. I havent heard anything about sudden acceleration since the airing of that show. Thats odd.;)

[joenintiesc]

I have that feature on my 90 AOD. I never liked it because I couldn't start the car standing outside and leaning in. Also, back when I knew nothing about my SC and brought it to a mechanic for everything, occasionally the car would just sit there in their lot because nobody could figure out how to start it, or they thought something was wrong somewhere...:confused: :rolleyes:

But that always led me to believe it was something of a theft prevention feature, so I was glad to have it since I never had an alarm.

[TbirdSCFan]

Originally posted by MIKE 38sc
Yeah Dateline did a segment on this issue a couple of years ago... I havent heard anything about sudden acceleration since the airing of that show. Thats odd.;) What? Followup journalism after sensational journalism? What a concept. Most of the time, they just let companies like Audi simmer as getting the facts is a lot more work than making press. ;)

[pdennis93]

interesting tidbit that is semi relevant to the shifter interlock device....i found a sweet anti theft system for our cars on accident, a few weeks ago my mf switch was acting up and i couldnt turn the headlights off, well since it was 11pm and i couldnt get to the u pull till the morning to get a new one, i pulled the fuse under the hood for the headlights, next morning, i started the car, and tried to shift it out of park, it wouldnt.....i thought maybe my trans had seized or something (ive already lost od and 1 and 2 slip bad) so after trying a few times pulling it out of park not hard enough to break the shifter but pretty firm, i remembered the fuse, shut the car off, put the fuse back in, and then the car would shift out of park, so if i ever leave the car somewhere i could always pull the fuse, and activate the killswitch for the ignition, then the car would be virtually unstealable, lol

[92TBurnSC]

Until they read this thread. ;)

[Parker Dean]

Originally posted by MIKE 38sc
Yeah Dateline did a segment on this issue a couple of years ago.
They talked several owners of the suspected so called sudden acceleration cars into letting them install small cameras in the re vehicals in the hopes they would catch it in the act, well they caught it alright.
I never will forget this lady who thought she was hitting the brakes trying to stop as another woman walked across a mall parking lot. She pushed gently on the gas pedal like you would when you brake but instead the car sped up. She started screaming OMG the BRAKES and this time she STOMPED what she thought was the brakes to the floor and held them! Only problem was it was'nt the brake pedal she was hitting, it was the accelerator. Luckily before she ran the woman down you could see she caught what she was doing because she corrected it quick and got stopped. She was either extremely shook up and really did'nt realize what she was doing or she did know she made a mistake but would'nt admit to it.
She maintained that she was hitting the brakes even though the camera footage showed exactly what and where her foot was at all times. I havent heard anything about sudden acceleration since the airing of that show. Thats odd.;)

Well one thing is that newer cars have the brake-shifter interlock so that removes the majority of new/unfamiliar drivers from the possibilities of UA.

People won't believe it, and I didn't until I did it myself, that you really beleive you had your foot on the brake and the car was accelerating on its own.

In my case the car was idling in Park and I hopped in and pulled it into gear. I then covered the "brake" as the car moved forward out of the stall. I needed to brake and pressed with my right foot. The car accelerated sharply and with a mental "WTH!" I pressed the "brake" harder. The car accelerated even more which is when my racer reflexes took over and I killed the ignition. After I got the car stopped on the handbrake I got out since I was a bit shook up and everyone was looking at me like "~~~!" I got back in and the car operated normally.

I didn't understand then what had happened. It was a few weeks later with another MN12 that I understood. After the UA experience I had stopped just placing cars in gear without the brake and now depressed the brake before selecting a gear. Again, the car was idling and I hopped in to pull it out of the stall but this time I pressed the "brake" first. The engine raced. The initial thought was "that's a hell of a bad brake booster", quickly followed by "it didn't do that on the way in. Why not?" I then moved to get out and the engine stopped racing. It was then that I understood.

What's striking about the whole thing is just how hard it is to realize what you're doing when mistaking the accelerator for the brake. You'd think it would be blatantly obvious and so did I but experience has taught me that the old saw about perception being reality is true.

[David Neibert]

I never really had a problem with the pedals, but apparently my wife did. About 8 years ago we were driving home very late one evening, and she was driving because I had drank a few beers. It's 2:00 AM and we exit the interstate and there are dual turning lanes. There was this small Toyota in the next lane (only car on the road).

The light turns green we both turn left onto the overpass above the highway and my wife is on the gas pedal a little to hard (slightly damp pavement) and the back end breaks loose. She quickly lets off the gas and then floors it. My eyes were as big as silver dollars and I'm screaming to her..let off the gas...she screams back..."I'm not on the gas..I'm pressing the brakes".

We hit the Toyota and knocked them sideways...she still has the gas pedal floored and the tires and engine are screaming louder than I am. We do a couple figure 8s somehow avoiding the sides of the overpass we are on, and hit the Toyota two more times..as the SC is swinging around for yet another run at the poor little Toyota, the engine suddenly dies from the inertia fuel cutoff switch (Thank You God).

It was alot like two cars doing donuts and bouncing off of each other. The SC was a mess and had damage on the front, rear and one of the sides. The Toyota was worse but nobody was hurt. The young couple inside the car was returning from a wedding reception and were pretty shaken up, because they couldn't understand why we kept hitting them over and over. I got pissed because she wrecked my SC and I walked down to a gas station for coffee, leaving her there to deal with the police.

When I got back the cop was scratching his head trying to re-construct the accident and actually was giving the kids in the Toyota a hard time. Lucky for us he didn't issue a ticket. It was the strangest damn wreck I've ever been in and until now I had never considered that the pedals are positioned different.

Maybe it's time I apoligise for leaving her at the accident scene.

David