Sitting at a stop light yesterday for about 3-4 minutes, it crossed my mind as to why do you want to sit at a stop light idling on all 8 cylinders. I think GM's programming for the V4/V8 mode needs some tweaking...and I hope when they do it you can simply take yours into the dealer for a plug-in update.

 

The engineers at GM must be idiots.

In your spare time take one of your V8 engine equipped vehicles and unplug 4 of the spark plugs while it idles and then report back to us on your findings.

 

Its a good idea. Used in the elder BMW 750i V12 by push of a button. Big relief when a friend of my brother thought his V12 was a little slow and suddenly read about that button. Just like the new M3 also cuts out alternator and etc when under heavy accelleration.

 

Somebody's touchy. Sounds like a case of the Mondays...

 

There are times when I'd want all 8 cylinders ready off the line, but then there are times when 4 is good enough. Maybe they should deactivate 4 cylinders at idle unless you're towing something.

 

A V8 engine will not idle on 4 cylinders.
If you don't believe me try it.

 

When I am cruising down a hill with zero throttle in V4 mode and the RPM'sare thesameas when I am sitting still, I guess the engine has actually stalled out on me...BS that it won't idle on 4 cylinders - I do it everyday on my way home..no gas, RPM same as when car is sitting still coasting down a hill in V4 mode.

Regarding off the line response....all these 'driveby wire' cars have a hesitation whenyou punch it off the line...if you punched it from a stand still,it would instantlygo into V8 mode and you would not feelthe transition...just likewhen it switches between v8 and v4 in normal driving...

Not sure about the engineers being idiots, but I am pretty sure about someone acting like one....

 

ZX is right, a V8 will not idle at 500RPMs with only 4 plugs firing. My truck runs at 1200 rpms when I am coming to a stop once I hit about 20MPH it switches to V8 and the idle will drop below 1200RPMs.

 

I thought that you were talking about "sitting at a stop light"?


Now are you talking about coasting down or idling at a stop light?
As soon as figure out just what it is that you're talking about be sure let us all know.