Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[tunnie]

off topic question, but on drive by cable engines (e.g 2.5)

Can tech2 set the rpm to a set level, say, 2,000 rpm for 5 mins?

[JamesV6CDX]

off topic question, but on drive by cable engines (e.g 2.5)

Can tech2 set the rpm to a set level, say, 2,000 rpm for 5 mins?

I doubt it - no way of letting air in...

[TheBoy]

off topic question, but on drive by cable engines (e.g 2.5)

Can tech2 set the rpm to a set level, say, 2,000 rpm for 5 mins?

Tech2 can adjust idle, but not that high.  Range is similar to DBW engines.

Of course, you could always adjust throttle cable to be far to tight

[TheBoy]

off topic question, but on drive by cable engines (e.g 2.5)

Can tech2 set the rpm to a set level, say, 2,000 rpm for 5 mins?

I doubt it - no way of letting air in...

So what controls ICV then

[Kevin Wood]

Can't really think of any advantages of DBW. Easy cruise enable with right equipment. Less clutter under bonnet perhaps?

It allows the engine management to implement some more efficient strategies, such as opening the throttle wider, advancing the ignition and using a leaner mixture when you're cruising. It can also dashpot the throttle electronically so if you stamp on the pedal or lift off suddenly it controls the rate of movement of the throttle so the fuelling doesn't lag behind the airflow, resulting in cleaner emissions. (and cr@p throttle response when you blip it!)

.. but from a driver's point of view it makes little difference.

you could say DBW is safer

It will have dual redundant position inputs from both the pedal and the throttle so if the two go out of sync it knows about it and shuts the throttle. If the throttle doesn't respond to the command to shut it it will limit the revs by cutting injectors, and if you hit the brakes it will also cut the power, which explains TDs observations. It ought to be pretty difficult to have an uncommanded full throttle passenger ride, but we are talking about software doing all this :-/

I remember a story about a Laguna 2 taking its owner for a rapid tour of the French autoroute network, but that's porobably urban myth, or a poor excuse for speeding

Kevin

[TheBoy]

you could say DBW is safer

It will have dual redundant position inputs from both the pedal and the throttle so if the two go out of sync it knows about it and shuts the throttle. If the throttle doesn't respond to the command to shut it it will limit the revs by cutting injectors, and if you hit the brakes it will also cut the power, which explains TDs observations. It ought to be pretty difficult to have an uncommanded full throttle passenger ride, but we are talking about software doing all this :-/

I remember a story about a Laguna 2 taking its owner for a rapid tour of the French autoroute network, but that's porobably urban myth, or a poor excuse for speeding

Kevin

Yes, exactly, how well are the error routines debugged.  In my experience of what the ECU does under error conditions....

But the 'failsafe' on the cable systems is just a spring  :-/

[Ken T]

One disadvantage of DBW is : In my old 2.0 GLS manual, if I needed to accelerate in a hurry, I merely put the foot down, and she would go. In my current 2.2 Auto, if you put the foot down cause some idiot in a BM is paying little regard to the 30 limit, the car sort of stops and thinks for a second "ah he wants to go a bit faster does he?, have to think about this, right lets put in a bit more fuel, and open the air intake a bit". I  recon the DBW electrons are a bit slow, sod this speed of light stuff.   And that's after a major tune up from Mark DTM  

[TheBoy]

One disadvantage of DBW is : In my old 2.0 GLS manual, if I needed to accelerate in a hurry, I merely put the foot down, and she would go. In my current 2.2 Auto, if you put the foot down cause some idiot in a BM is paying little regard to the 30 limit, the car sort of stops and thinks for a second "ah he wants to go a bit faster does he?, have to think about this, right lets put in a bit more fuel, and open the air intake a bit". I  recon the DBW electrons are a bit slow, sod this speed of light stuff.   And that's after a major tune up from Mark DTM  

Yeah, I reckon my leg is faster than the servos...

[tunnie]

you could say DBW is safer

It will have dual redundant position inputs from both the pedal and the throttle so if the two go out of sync it knows about it and shuts the throttle. If the throttle doesn't respond to the command to shut it it will limit the revs by cutting injectors, and if you hit the brakes it will also cut the power, which explains TDs observations. It ought to be pretty difficult to have an uncommanded full throttle passenger ride, but we are talking about software doing all this :-/

I remember a story about a Laguna 2 taking its owner for a rapid tour of the French autoroute network, but that's porobably urban myth, or a poor excuse for speeding

Kevin

Yes, exactly, how well are the error routines debugged.  In my experience of what the ECU does under error conditions....

But the 'failsafe' on the cable systems is just a spring :-/

Which is missing on the Elite  

[TheBoy]

you could say DBW is safer

It will have dual redundant position inputs from both the pedal and the throttle so if the two go out of sync it knows about it and shuts the throttle. If the throttle doesn't respond to the command to shut it it will limit the revs by cutting injectors, and if you hit the brakes it will also cut the power, which explains TDs observations. It ought to be pretty difficult to have an uncommanded full throttle passenger ride, but we are talking about software doing all this :-/

I remember a story about a Laguna 2 taking its owner for a rapid tour of the French autoroute network, but that's porobably urban myth, or a poor excuse for speeding

Kevin

Yes, exactly, how well are the error routines debugged.  In my experience of what the ECU does under error conditions....

But the 'failsafe' on the cable systems is just a spring :-/

Which is missing on the Elite  

It wasn't on Sunday?

[tunnie]

i thought it was? - or was it the tiny clip!?!?

[TheBoy]

i thought it was? - or was it the tiny clip!?!?

Ah, yes, both your cruise cable E clip and your throttle cable clip are missing.  But the throttle spring is still there

[Andy B]

One disadvantage of DBW is : In my old 2.0 GLS manual, if I needed to accelerate in a hurry, I merely put the foot down, and she would go. In my current 2.2 Auto, if you put the foot down cause some idiot in a BM is paying little regard to the 30 limit, the car sort of stops and thinks for a second "ah he wants to go a bit faster does he?, have to think about this, right lets put in a bit more fuel, and open the air intake a bit". I  recon the DBW electrons are a bit slow, sod this speed of light stuff.   And that's after a major tune up from Mark DTM  

This sounds similar to SWMBO's auto Astra 16v 1.6 (DBW) When I hold my car on the foot brake it will creep against the brakes, my wife's car doesn't. As you lift your foot from the brake it's as though the gearbox needs a second or so to 'switch back on' so if you're too quick hitting the throttle after lifting the brake pedal you get a sudden thud as the gearbox catches up.

[Taxi_Driver]

One disadvantage of DBW is : In my old 2.0 GLS manual, if I needed to accelerate in a hurry, I merely put the foot down, and she would go. In my current 2.2 Auto, if you put the foot down cause some idiot in a BM is paying little regard to the 30 limit, the car sort of stops and thinks for a second "ah he wants to go a bit faster does he?, have to think about this, right lets put in a bit more fuel, and open the air intake a bit". I  recon the DBW electrons are a bit slow, sod this speed of light stuff.   And that's after a major tune up from Mark DTM  

This sounds similar to SWMBO's auto Astra 16v 1.6 (DBW) When I hold my car on the foot brake it will creep against the brakes, my wife's car doesn't. As you lift your foot from the brake it's as though the gearbox needs a second or so to 'switch back on' so if you're too quick hitting the throttle after lifting the brake pedal you get a sudden thud as the gearbox catches up.

Thats normal......i used to have a v6 vectra auto......that did the same.....the ecu puts the g/b into N after about 5 secs if you dont move and your foot is on the brake......imagine the thump from the autobox when stamping on the throttle with a v6!