On Tue, 02 Mar 2010 08:08:52 -0500, wrote:

On Mon, 01 Mar 2010 20:01:21 -0500, wrote:

On Mon, 01 Mar 2010 17:55:24 -0500, wrote:

On Mon, 01 Mar 2010 16:37:24 -0500, wrote:

On Mon, 01 Mar 2010 11:49:48 -0600, dpb wrote:

LouB wrote:
Tony wrote:
mm wrote:

My friend had a Rav 4. I don't know what that is. Today my friend
says it has unintended acceleration, but only a little. !!!!

If I owned one of those Toyota vehicles affected, I would install an
auxiliary engine kill switch before I drove it again.

And when you kill the engine you loose both power steering and power
brakes.

Better than uncontrolled acceleration, undoubtedly.

Unless they're fully hydraulic steering (of which I know of no autos; do
have such a tractor), it's only the power assist that's lost, not
steering. Same w/ the brakes, it's only the power assist.

The actual recommendation is to shift to neutral and let it over-rev;
what possibility/likelihood of blowing an engine is I've not firm
estimate but if that happens you're in same boat anyway...

Probability of blowing the engine is much less than 2% - the compiuter
shuts off fuel at about 4500 RPM in neutral.

Unless of course the runaway condition is being caused by a fault in
the computer!

Would need to be a compound fault, as the rev limiter has no
connection to the throttle. It shuts off injectors.
SO - even if the "unintended accelleration" problem IS a computer
glitch, it would still not blow up if put in neutral.......


If the computer is malfunctioning, then I think you can allow for the
possiblity that it may not do what you expect on many fronts. We don't
know the nature of what is causing the fault. Is it an unreliable
oscillator? A bad ground? Leaky capacitor? Power fluctuations?
Electrical noise? Any of those things could have widepread
repercussions in the computer.


Anything that stops the clock would, by necessity, stop the engine
because the clock is required to fire the injectors and time the
spark. Absolutely IMPOSSIBLE for the engine to run if the oscillator
(clock) of the ECU was to fail.
Pretty much the same with a bad ground - as the injectors are ALL
powered externally and grounded through the ECU. Also, all the sensors
go to higher voltage as the input increases. A ground (Other than the
wired signal ground for each 3 wire resistance type sensor) is not
required on the majority of sensors, and if that ground went bad the
reference voltage would go out of spec, throwing a code or the sensor
would be detected as an open circuit (also an out of range value),
throwing a different code.
About the only thing external that could be causing an accelleration
problem would be digital noise entering the system as RFI that just
happened to be exactly the right frequency and amplitude , at exactly
the right place, to fool the computer into thinking it was a
legitimate signal.

Extremely unlikely - not at all like the analogue type fuel injection
computers used on the oldD-Jetronic system like the VW412. (and EFI
SuperBeetle)


Maybe it will shut off the fuel, and maybe it won't. Toyota insisted
that the computer would have thrown up an error code after an alleged
runaway incident. It has been proven conclusively that that is not
correct. An engineer has demonstrated live on TV that he can cause the
computer to go into runaway acceleration, and it does not throw up any
trouble codes as a result.


And how is he "throwing it into runaway accelleration"??????

I don't know the specifics. He has equipment connected to points in
the computer that allow him to manipulate it.

I guess by applying hi or low logic signals to various circuits.