Cruise control and trip computer

[Allan-]

How does the Cruise control pick up speed and work out what speed your doing etc.
Also how is Mpg worked out on the Clio 182, as my trip computer tells me im doing 60 mpg and when i work it out manually its actually about 39 (engine has been remapped on the standard ecu)
The speedo works and the miles are correct in the trip computer.
Also going 3rd party ECU are you able to keep your functions on the trip computer with cruise and speed limiter etc

 

[JoedotwasT5phy]

Well its Fly by wire so bascially the engine is told what it needs to do to maintain 70mph - do you need any more info than that? the MG is again a simple calculation of gallon/lites of petrol used to distance travelled.

If you go piggy back ECU then you need to retain the original ECU anyway for most of the cars functions (unless you want a complete re-wire of the car?) but i don't think the car will retain cruise etc.

 

[Dan519]

as above really. GEN90 retains all functions of the trip computer and cruise control, except on conversions that require cable throttle (ITBs) where you lose cruise. My trip computer still works

 

[Allan-]

Intresting ok assuming the ECU is standard (remapping shouldn't be an issue) and its still working on fly by wire (which it is) then the cruise should work.
Ok as for Gallons / liters used, does the ecu work that out via assumption or does it actually measure it somewhere ?


As the problem i am having i, put the CC button up and get the green light but as soon as i start moving the green light goes out and never comes on, the trip computer tells me im doing 22mph average while sat at 60, so i can assume i have a weird fault here.
Which is probably why the trip computer is producing such wrong mpg figures.
So where does it pick the speedo up from ?
I'm used to having a williams with a speedo cable off the box. (only got the 182 at the weekend)

Also Dan are you the same person who fixed LA's williams when it popped at the Ritz last summer. As i remember she run a Danny and the Recovery truck was going to bedford...

 

[Dan519]

consumption is calculated by injector times and a big long algorhythm that takes all sorts into account. No idea on the rest of that fault, sounds like it's got something odd gone on, maybe had a remap with the wrong firmware version used so the ecu isn't functioning fully?

Yes that's me, She's my ex. Got her 3 here at the moment actually

 

[Allan-]

ah well not sure, will have a play about and see what comes. Not a great loss if the curise is gone