Run away cars

You are assuming that his definition of "drive by wire" on his Saturn excludes the operation of the transmission. Maybe it does, but he didn't say one way or the other so we don't know.

=A0> I've never heard

Surely you know there have been reports of exactly that by people experiencing the Toyota runaway problem. Are they telling the truth? Maybe not, but to just dismiss them outright without a complete understanding of how the transmissions are designed, actually work, perform under full throttle conditions, examining the transmissions from the runaway cars, etc, I'd say is premature.

Reply to
trader4
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wrote

Yes, we do know. Linkage is mechanical.

Reply to
Ed Pawlowski

I can't say either way for sure as I do not have the shop manual yet (no need for at least another 2 years). When the shifter is put in "M" manual while the transmission is in any gear other than 1st the transmission drops down a gear. If the car speeds up or down the transmission will continue to shift albeit a little more aggressively (a more sportier feel). If the shifter is put into "M" while the transmission is in 1st or stopped the car will not shift until you manually shift it with a toggle switch on the side of the shifter (sort of a clutch-less manual mode - where all 6 gears are available). It is this mode that makes me wonder as this has to be a by wire shift mode as there is no movement of linkage only the pressing (rocking up or down) of a toggle switch).

I know the computer plays a roll in the shifting because the shift patterns can be changed by reprogramming the computer. I believe there was a service bulletin for the 4 cylinder model that fixed a shift pattern problem on the smaller engine. The solution was uploading a patch to the computer.

From what I have read in a Saturn news group I believe the shifting is by wire from the shifter but can not say if it goes to the computer before the transmission or if the computer only monitors the transmission and has the ability to make adjustments to performance?

Reply to
Ned Flanders

Just as I thought. I don't know why some people want to rush to judgement without having all the facts. Obvioulsy there are a LOT of different cars out there and without factual data, no one here knows what exactly is or isn't in any of them.

Excellent example that things may not always be as simple as some people would have us believe. Clearly from what you describe, there is at least some kind of electrical control over the transmission.

Another excellent point.

Reply to
trader4

Unless I misheard it on the news, the Sheriff there said "I don't _think_ it is a scam". Obviously it is being looked at closely.

Harry K

Reply to
Harry K

I heard that too. But of course that is what the sheriff in the Balloon Boy case said at first too. The more I hear, the more suspicious it sounds. Fox News did a good job investigating his background. With a bankruptcy for $700K a year ago, no payments on the Prius for several months, it looks more likely a hoax to me.

Reply to
trader4

Esoterica: This bit my BIL. You could not put a 37 engine into an earlier chev without changing the motor mounts. The 37 was shorter. I knew this as my dad had to do the conversion when he changed the motor on his 34 1 1/2 truck. My BIL tried it on a ?36? PU back in the

70s

Harry K

Reply to
Harry K

wrote

But you don't know what I know or what cars may be sitting in my driveway.

Reply to
Ed Pawlowski

Actually more vehicles use the CVT. My daughters Saturn Vue has a CVT, not sure if they all do? I think some other american made cars have them, but not sure. A lot of "maybes" here but I think the CVT has been used for some time now in sub compact foriegn cars not available for import to the US.

Reply to
Tony

Except the castr iron wonder and the early stovebolt ALSO had an oil pump. (as did the earlier 4 cyl Chevies)

Reply to
clare

Reply to
clare

IF the car has a CVT, there MAY not be a mechanical linkage. I have not been able to find a reference for sure, and have not physically looked at one to see.

Anything that has a plantary gear multi-ratio transmission DOES have a mechanical way of putting it in neutral that is totally separate from the electronic controls.

Reply to
clare

The electronic control on every electronic shift transmission I am familliar with (which is quite a few) controls the shifting between forward ratios by switching hydraulic pressure with electrically controlled solenoid valves. Pre-computer controlled versions of the same transmissions used a hydraulic valve body which controlled the same hydraulic fluid flow by hydraulically opperated spool valves that balanced throttle and governor pressures against springs and each other.

Both types of transmissions, however, still have a "manual valve" which controlld whether the transmission is "engaged" or in "neutral", and whether it is in forward or reverse.. There may be some that also use a solenoid for reverse application as well the manual valve, but the interesting thing is, if you don't have the manual valve out of the neutral position, it doesn't matter what happens with the solenoid valves, the car isn't going anywhere. Also, it doesn't matter if the manual valve is in drive, if the solenoids are not actuated, and in the right pattern, the car isn't going anywhere.

The reprogramming changes WHEN the solenoids are actuated by requiring more or less governor pressure, or more or less throttle pressure to control the line (or apply) pressure.

Some "electronic controlled" transmissions only have electronically controlled governor and throttle pressures and still use a more or less conventional valve body.

Reply to
clare

Yes, the pre-37 "cast iron wonder" was a different engine than the "stove bolt", and I'm told the cast iron wonder would interchange with the pre-1929 4 cyl. (the 1928 hood was long enough to take the six as the 1929 engine was originally slated for the '28)

Reply to
clare

But the normal CVT is different from Toyota's CVT which is ONLY used in Hybrid Synergy Drive.

There ARE CVT transmissions used in other hybrid and non-hybrid cats, but they use a metal belt and variable pully setup similar to a snowmobile drive system (or variomatic drive)

Reply to
clare

_Stopping Procedure for Toyota Hybrid Vehicles_

Video:

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According to Toyota, of course.

Seems some procedures take a second or three. Like holding the off button.

Reply to
Oren

More speculation and over reaching. How the hell can you know what all cars do or don't have? You're the guy that tried to tell us that most modern cars have only two computers and some have only one. I provided you several credible links that say that is total nonsense.

Reply to
trader4

So 1 1/2 seconds to put it in neutral and 3 seconds to shut it off. Say 5 seconds to do both. Say it takes you 10 seconds to figure out you need to shut it down, that;s still only 15 seconds.

Reply to
clare

Say what you want. I've been in the business for a long time. All you can say is nobody knows. Well, thre are peoiple out there who DO know

- and I talk with a lot of them.. I don't care what you think.

Reply to
clare

I 'figger' anyone taking a teen driving test would know all this.

Reply to
Oren

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