Stuck and/or Accelerating Throttles

[sparks]

  I once owned a 1962 Pontiac Catalina. The throttle system was a series of rods and counter motion levers leading from the footfeed (bet you haven't heard that in a whille) to the carburetor. The whole return to idle was controlled by a single spring attached to the carb. IIRC one of the counter motion levers was mounted at the rear of the left cylinder head, which meant that a sudden 'flooring' of the throttle would cause the engine to twist ever so slightly in the motor mounts and bind the linkage on occasion. Fortunately, there  was enough room to stick my foot under the pedal and back out. After a bit a snooping around I discovered that the mount for that lever had been bent in a prior engine removal/installation. A couple of well placed whacks with a machinist's hammer cured that.


Then came the fateful day that the throttle return spring broke and again found myself sticking the toe of my shoe under that big ol' gas pedal.

Toyota's problems are nowhere this simple.



End of part one....sparks

[sparks]

Part Deux.

I currently own two vehicles, a 2002 Ford Ranger V6, and a 2005 Mustang GT. Two Fords and engineering worlds apart.

First the Ranger. Fuel injected V6. Nineties technology. The throttle linkage has been replaced by a 'cable' which now leads to something called a throttle body. And it has a return spring. Does nearly the same thing that the old carbed systems did. Mechanical linkage.

The cruise control is a vacuum servo operated system that works in tandem with the throttle; when you set the cruise, you can feel the pedal just ever so slightly 'adjust'. Some of these systems have been known to 'over adjust'. A touch of the brakes would typically shut the cruise off.

Apart from the electronic fuel injection, this is how throttles and cruise controls worked.......they utilized some type of mechanical connection to perform such fuctions. (to be fair, I know there are exceptions)


And then came the elecronic throttle control.......the accelator by wire.....electricity.


End of part two.......sparks

[waggin]

Yup, drive-by-wire systems and their attendant sensors, controls, etc. don't respond well to BFH repairs.

[sparks]

Part Three

I ordered the Mustang from the local dealership early in '05. I wanted what I wanted and got it; it was delivered Memorial Day weekend. The intial drive was a blast.....the handling......the stiff ride... and the touchy throttle......and I mean touchy. Maybe a third depression (just guessing) of the 'footfeed' and this car would blast to 60mph before I knew it! It was as if the throttle had something on it akin to 'power steering'.......nearly effortless.......that increasing spring resistance my right foot was used to after forty years of driving was no longer there. And then I investigated; the mechanical linkage is gone. A sensor of some description at the footfeed. The signals from that sensor are fed to many electonically managed systems..throttle....cruise....transmisssion.

My point being, modern day footfeeds have no mechanical linkage...only sensors(s). And wires. Nothing that could make them 'move' on their own.


Didn't that dope in the Prius claim that the pedal felt funny under his foot and then the car floored itself???



sparks

[glenn kangiser]

I tend to agree with you, Sparks, but I found this also.  Maybe they used Chinese electronics?  Or maybe the lady stepped on the wrong pedal and is too embarrassed to admit it.

http://www.worldcarfans.com/110031125046/another-toyota-prius-acceleration-incident-in-new-york

[glenn kangiser]

This one looks more like the conspiracy type to damage Toyota as it says there are an increase in problems but then goes on to only relate the first problem reported again.... negative propaganda....

http://www.worldcarfans.com/110031025026/runaway-toyota-prius-incidents-arise---us-joins-toyota

[glenn kangiser]

Stuck throttles.... I remember my old 58 Ford and 56 Merc with 312's.  They would break the motor mount on the left side I think it was due to torque over the years.  Step on the gas to peel out and the motor would jump about 4 inches up on the left pulling the throttle wide opened. 

We didn't think we needed to sue someone.  We always thought we needed a new motor mount.  [ouch]

[diyfrank]

I had plenty of old fords with a chain on the left side to keep the engine from breaking the mount. It was a trip to give it some pedal and have it floor it self. Of coarse you don't think to put it in neutral or turn of the key.

[glenn kangiser]

Seems I always stood on the brakes to keep from throwing a rod... [ouch]

[diyfrank]

http://www.youtube.com/watch?v=6B2e6D484v8

[Sassy]