Slight corrrection on VSS

[Roger Heflin]

On Tue, 5 Jan 1999, steve ravet wrote:

> 
> 
> 
> That's decel cutoff, isn't it?  I used to own an '89 vette with the
> digital dash.  One of the many things the dash would do was read out
> instantaneous mpg.  I distinctly remember that if you let off the gas,
> say in second gear and around 30 mph (like slowing for a stop sign),
> about a half second after getting off the gas there would be a small
> lurch, and the mpg meter would peg at 99.  When you slowed to the point
> that rpm was almost idle, like 1200 or so, there was a much more
> noticeable lurch and the mpg meter would drop to a reasonable value. 
> The service manual also confirmed that the ECM would shut off fuel
> delivery under some deceleration conditions.  Mine was standard, does
> the automatic bin do this?  seems like an auto could stall without the
> drivetrain keeping the engine turning.
> 
> --steve

I did notice there is some code in the TCC lockup routines that do
things different based on coasting above or below a certain speed.
Also torque convertors work just fine in reverse, so at higher speeds
the torque convertor will still be turning the engine just not a 1:1
speed.  At lower speeds the computer may be doing something to keep it
from stalling.  Mine has not dropped below idle speed while I am
coasting so it is doing someting.

		Roger
		93 Z28 A4