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[BazaJT]

Only Omegas I've owned or indeed driven-the present one and another a good few years ago-have been 3L Elites.Obviously these have throttle cables,so as much out of curiosity as anything else what are the advantages/disadvantages of the drive by wire system as fitted to 2.6's? and 3.2's and why did GM feel the need to fit such a system?

[05omegav6]

Dbw allows for far more efficient engine management... with the ecu controlling the throttle rather than reacting to mechanical inputs... cruise control being a case in point

Also less gubbins in the engine bay

[laney101]

as harris said allows better management to be run for more efficiency. how ever after driving both the lack of feel in a DBW throttle can be a tad annoying very light just a pedal in free air.

do prefer feel and control of a cable throttle but it works well and is very reliable. they physically better

[zirk]

More stuff to go wrong, more flashing lights on the dashboard, more money for the Service Center's.

It will never catch on, bit like that power steering gismo and them servo assisted brake thing'y, is all for wimps. 

Christ, there be making gearboxes without clutch peddles next.   

[BazaJT]

I'm led to believe they've also come up with a new fangled system for the gearboxes that you need 3 pedals for.Think they've called it synchromesh? and they say you no longer need to double de-clutch to change gear!It'll never catch on

[TheBoy]

and why did GM feel the need to fit such a system?

Cost.

Everything about in-life "enhancements" in cars are due to cost.

[Andy B]

.... and why did GM feel the need to fit such a system?

Do any new cars still have a throttle cable? I doubt it .... 

[YZ250]

......
do prefer feel and control of a cable throttle but it works well and is very reliable. they physically better

I'm not saying that DBW system is infallible but many years ago I was bearing down on a roundabout at a rapid rate of knots, after just leaving a bypass, and when I lifted my foot off the accelerator nothing happened. The accelerator pedal was firmly planted on the carpet and the car had the power to outdo the brakes when I tried to stop. I had no option but to turn the key back one notch to kill the engine, but this also took away my servo assistance for the brakes and I had no power steering. Just as I approached the empty roundabout at speed, I turned the engine back on to regain my brakes and steering, the car pulled like a train as I had banged it down to gears to aid stopping but I did manage to take the straightest exit off the roundabout. I turned the key off again and pulled over.
The throttle cable had frayed and would not return up the outer cable, so I for one am not sorry to see DBW on cars. 
I'm just eternally grateful that my wife was not driving the car on that day. 

[TheBoy]

......
do prefer feel and control of a cable throttle but it works well and is very reliable. they physically better

I'm not saying that DBW system is infallible but many years ago I was bearing down on a roundabout at a rapid rate of knots, after just leaving a bypass, and when I lifted my foot off the accelerator nothing happened. The accelerator pedal was firmly planted on the carpet and the car had the power to outdo the brakes when I tried to stop. I had no option but to turn the key back one notch to kill the engine, but this also took away my servo assistance for the brakes and I had no power steering. Just as I approached the empty roundabout at speed, I turned the engine back on to regain my brakes and steering, the car pulled like a train as I had banged it down to gears to aid stopping but I did manage to take the straightest exit off the roundabout. I turned the key off again and pulled over.
The throttle cable had frayed and would not return up the outer cable, so I for one am not sorry to see DBW on cars. 
I'm just eternally grateful that my wife was not driving the car on that day. 

In my experience, the electronic throttles are less reliable than cable, *BUT* unless the servo jams, do tend to fail towards idle . That said, the failsafe for cables is throttle closed as well.

[Nick W]

In my experience, the electronic throttles are less reliable than cable, *BUT* unless the servo jams, do tend to fail towards idle . That said, the failsafe for cables is throttle closed as well.

Failure of the throttle pedal sensor is common on Astras and A3/4 Audis, and as you say, they fail closed.
Frayed throttle cables can jam the throttle open, which is what happened to me. But turning the engine off is a poor solution compared to shifting the transmission into neutral.

[Kevin Wood]

In my experience, the electronic throttles are less reliable than cable, *BUT* unless the servo jams, do tend to fail towards idle . That said, the failsafe for cables is throttle closed as well.

Failure of the throttle pedal sensor is common on Astras and A3/4 Audis, and as you say, they fail closed.
Frayed throttle cables can jam the throttle open, which is what happened to me. But turning the engine off is a poor solution compared to shifting the transmission into neutral.

Yep. Been there, done that, thanks to Westfield's bizarre throttle pedal design. Let it bounce off the rev limiter until you are out of danger.

[Andy B]

I've had the throttle return spring fail  just lifted the pedal with my foot though 

[Nick W]

Failure of the throttle pedal sensor is common on Astras and A3/4 Audis, and as you say, they fail closed.
Frayed throttle cables can jam the throttle open, which is what happened to me. But turning the engine off is a poor solution compared to shifting the transmission into neutral.

Yep. Been there, done that, thanks to Westfield's bizarre throttle pedal design. Let it bounce off the rev limiter until you are out of danger.

Mine was a Chrysler Sunbeam Ti, where the only design criteria for the factory twin DCOE linkage was to use the stock single Stromberg throttle cable. Replacing the linkage and cable with the genuine weber setup was the best thing I ever did to the car.

[YZ250]

In my experience, the electronic throttles are less reliable than cable, *BUT* unless the servo jams, do tend to fail towards idle . That said, the failsafe for cables is throttle closed as well.

Throttle had jammed wide open. 

Frayed throttle cables can jam the throttle open, which is what happened to me. But turning the engine off is a poor solution compared to shifting the transmission into neutral.

With hindsight I'd probably agree Nick. You have just a split second to react and this was my reaction, albeit possibly a bad reaction.    There was no rev limiter back in those days so I'm guessing the engine would have self destructed.

Yep. Been there, done that, thanks to Westfield's bizarre throttle pedal design. Let it bounce off the rev limiter until you are out of danger.

No rev limiter back in those days Kevin, not sure it had even been invented.  Car in question was my Capri 3.0S which I owned for just over six years, so the event was quite some time back. 

[zirk]

No rev limiter back in those days Kevin, not sure it had even been invented.  Car in question was my Capri 3.0S which I owned for just over six years, so the event was quite some time back. 

They were quiet nippy,  a friend of mine had a 3.1 RS years ago.