Megasquirt Support Forum (MSEXTRA)

Hi all,

I've just taken delivery of my new Q818XT, and took it out for a spin after hooking it up to TunerStudio and adding speedo/instant mpg/average mpg dials to my dashboard. When I went out for a drive, The instant MPG was saying 99 and the average saying 0 for the whole 2.5 mile run. I'm not sure how accurate the speedo was, it seemed that sometimes it would be tracking the physical speedo, sometimes it would be displaying arbitrary fixed speeds - I couldn't look at it all the time since it was on the passenger seat next to me

Other than hooking the GPS up via bluetooth and configuring it in TS (v3.0.21) is there anything else I need to do? All the pages I've found say that's all I need to do.

Attached MSQ and log.
I've removed the first quarter of a mile or so of the log; that's just me getting out onto the main road from my house. (plus I had to bring it under the 1Mb limit!)

Cheers,
KEv.

Did you input all the data in the 'performance and economy' section in the data logging menu on tuner studio.

How accurate the speedo is and which input you are using for the speedo is everything...

On the main menu go to:
Data Logging --> Performance and Economy Fields

Make sure it is set up in there.

Thanks guys

I went and checked there - the primary injector size was set to 0. I guess that's why the mpg values were out!
I assumed that the fuel usage would be calculated from the injector size under Basic/Load Settings->Engine and Sequential Settings.

I'm busy this weekend but I'll try that when I get a chance and see if it makes a difference.

Cheers,
Kev.

Assuming you have a good VSS and are using just one set of injectors (no staged injection) Note that the GPS stuff has about a 1 sec delay and messes with the calc on hard accel.

Instantaneous MPG is real close to

c * VSS / Duty Cycle

Where c is a constant to get the units to work out to the units you want. I use the average function in MLV to figure out the constant. I found this when I was trying to figure out how Harley was doing this to the dash of the newer bikes. It was almost spot on to what they were reporting in the data logs and displaying on the dash.

Andy

It's working now - just had to set the injector size. I'm getting about 16mpg on average! Not bad for a Defender..