Drive by wire (DBW)????

Control of something by electrical impulse over a wire rather tugging on a cable-- like in the old days there was one from your gas pedal to the butterfly in the carburetor that opened it wider when you stomped down. When you tromp on the gas pedal these days, it sends a signal to the fuel injector and fuel pump to step up the flow.

"Andy" wrote in news: snipped-for-privacy@pipex.net:

the steering is actuated by an electric motor that is controlled by a servo actuator loop at the wheel. They're trying to eliminate the power steering pump and reduce load on the engine.

IMO,not a good idea;if something glitches or fails,it WILL kill you. There's a reason FlyByWire F-16s got the nickname "Yard Dart".

On an F-16,F-15,F/A-18,you gain a lot of maneuverability,something important for fighter jets,but totally unnecessary for an auto.

"Richard Blaine" wrote in news:rvmdnYK2LPVs18ranZ2dnUVZ snipped-for-privacy@comcast.com:

actually,the ECU makes the injectors stay OPEN (duration) longer,thus more fuel flow.(by sensing throttle pedal position with a variable resistor)

In most cars, there is still a cable that attaches to the butterfly in the throttle body. Injector operation is controlled by the ECU based on the airflow measured through the throttle body or manifold, and assorted other sensors' input, rather than direct input from the pedal.

Actually, as I understand it, there is an electric pump to reduce the load on the engine, there is still a mechanical connection between the front wheels & steering wheel.....I could be wrong.

none of the above guys. drive by wire is simply having the throttle operated by a computer controlled servo. it means there is no mechanical connection to the pedal any more - just a sensor that acts as input for the ecu, and the ecu uses that in conjunction with a bunch of other info to calculate how wide to open the throttle. it's especially advantageous for automatics as it means you can de-throttle when the gear changes. injection really has nothing to do with it.

yes, electrically controlled power steering. that's not drive by wire.

"Justbob30" wrote in news:sY-dnRVP3Oqv7cranZ2dnUVZ snipped-for-privacy@comcast.com:

it would not be "drive by WIRE" then. for "drive by WIRE",the steering commands come through the wiring,not through any mechanical linkage.

And by top posting,you destroy any logical continuity of the thread.

jim beam wrote in news:07SdnVrMkfRj78ranZ2dnUVZ snipped-for-privacy@speakeasy.net:

No,"DRIVE by wire" is electrically controlled STEERING. You are describing "throttle by wire".

My 2003 Nissan Sentra SE-R SpecV has throttle by wire;the throttle plate is controlled completely by the ECU. Because of some wierd problem,my RPMs sometimes rev up to 1500-2000 RPM and hunt around there for a second,then slowly drop back to idle,without my foot even on the gas pedal.It's caused a CEL of "idle RPM too high".I either need a new PS pressure switch or new programming of the ECU(according to a service bulletin),which can of course only be done by Nissan dealers;....at some charge.

I might be able to get the reprograming done under a different safety recall at no cost.

Drive by wire means that the linkages in a system are not all mechanical. The system can be brakes, steering, throttle, etc.

I agree. In airplanes (that receive continuous maintenance) it's ok but not in cars many of which are driven by idiots or worse.

Give me a mechanical link to the function of steering, throttle and brakes anyday!

OTOH, the L1011 is a fly by wire plane with a perfect safety record.

JT

no such thing that i've ever seen on a civilian road vehicle. honda is simply mechanical power steering [just like any other car] but with electronic control on the degree of assist.

which is referred to, by honda and other manufacturers, as drive by wire.

not on its own it doesn't. throttle position is just one of many sensor inputs that the ecu uses to calculate injection duration. these also include:

oxygen sensor coolant temperature air temperature air pressure - manifold air pressure - atmosphere

throttle position is just part of the equation. if you want to check out how the math is done, read this:

still have one.

why? all a throttle does is control air. with a diesel, "throttle" doesn't even do that!

if you have hydraulic or air brakes, and most us have for at least 50 years, you have no direct mechanical linkage.

Hopefully, you have your answer but if not -

Drive by Wire typically refers to the electronic connection of the gas pedal to the engine - so when you push down on the pedal, it sends a signal to the engine control computer than you want to speed it. The control computer then uses a whole series of inputs to determine how to adjust the engine to meet your request. There isn't any mechanical connection to the engine from the gas pedal. This is noticeable, for example, when using cruise control - a DBW system won't cause the gas pedal to move as the engine speed changes to maintain the cruise setting. My Audi A4 has this feature.

Electric (or electronic) power steering simply replaces the hydraulic, engine-driven power steering pump with an electric pump that doesn't require being hooked to the engine. The steering is still a direct, mechanical connection, so that if the pump fails, you can still steer the car (albeit requiring much more force). I don't know that any cars currently made have a non-direct mechanical connection between the steering wheel and the front wheel, and would be VERY surprised to see that happen in the near future.

Dan D '07 Ody EX Central NJ USA

wow, cheers guys, look like i started something there, didn't I? lol

Thanks again I now have a little more understanding :-)

Thinking of buying a used 2.2 Diesel and noticed this wording and never seen it mentioned before.

Does anyone have a 2.2 accord? Your comments on the vehicle i would appreciate....

thanks aga>> Can you tell me what "Drive by Wire" is please, on new honda accord

Grumpy AuContraire wrote in news:8lL5j.211000$ snipped-for-privacy@bgtnsc04-news.ops.worldnet.att.net:

yes,and the L1011 gets constant maintenance and checks,and has triple redundancy in the flight controls.

Actually, the L1011 has four separate hydraulic systems.

You bet they're maintained. Such doesn't exist in the automotive world.

JT