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That's the first logical dissection of this issue I have seen. He makes a lot of sense.

Most cars today have some form of throttle control that the computer actually controls. I have not seen any discussion about that. It could simply be that the car's computer takes over during some malfunction and causes the car's "throttle" to go to full open.

Most cars today have some form of throttle control that the computer actually controls. I have not seen any discussion about that. It could simply be that the car’s computer takes over during some malfunction and causes the car’s “throttle” to go to full open.

Yes, that is exactly what it is.

I too was amazed to see very little discussion of this possibility.

How do I know?

Happened to me, in 1982, in one of my 3 Audis that I owned at the time since I liked them;

I was driving along a quiet rural road at 35 mph and suddenly the car just took off at 80+ mph - I was NOT stepping on both pedals, the cruise control just suddenly kicked in and the car took off at very high speed; quite surprising;so I stood on the brake pedal with BOTH feet and the accelerator pedal was released i.e. popped back up ... you could hear it pop up. ... actually, happened to me twice with my Audi 5000, twice in 8 years of ownership, but not my other two Audi cars.

I didn’t sue anyone. Didn’t even report it. Figured if it happened again I would just stand on the brake pedal with both feet and solve the problem myself.

I had purchased the Audi 5000 brand new from the dealer in Redondo Beach / Palos Verdes, where I was living at the time.

raybbr said:

Most cars today have some form of throttle control that the computer actually controls. I have not seen any discussion about that. It could simply be that the car's computer takes over during some malfunction and causes the car's "throttle" to go to full open.

I'm going to agree with ray here and explain why.

Mrs. Peet and I own a Japanese(*) car that has all the lovely "fly-by-wire" computer control. Since we are both adamant about owning standard X-mission v.s. automatic, both her car and my pickup are stickshift. That is significant since I noticed something on the "computer-controlled" car that the old carburated P/U didn't do which would be harder to detect on an automatic.

THIS: Accelerating hard (say uphill) and go to shift. Clutch in, foot backs off gas pedal, engine continues to rev up for a short time. Length of time on the extra rev. depends on how hard the acceleration was.

I complained. After a firmware upgrade, some testing, and manual reading, the service manager explained to me why it was happening, and could not be stopped: Hard acceleration pours a lot more fuel onto the cylinders than lesser acceleration so when one backs off the gas pedal, there is still rich air/fuel mixture in the cylinders. The computer detects this and continues high revs to burn off the excess fuel cleanly. They call it "flaring".

(Those of you old enough will remember carburated engines backfiring under rich mixture/sudden deceleration conditions.)

Hypothetical: Sensor in the exhaust system goes bad and tells the (cursed) computer the mixture is WAYYyy too rich and the computer tries to burn off the excess.

HTH, HAND
Peet

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* Let's not quibble about assembled/most parts made in/etc. It is Japanese branded.