Digital RPM and Coolant Temp Display

Looking very interesting now.

kiteman wrote:

Following on from this thread, I've been working on a removable unit for OSG and finally have it finished, here's a picture of how it looks fitted to the top of my dash.



It's showing Engine Coolant Temperature, RPM and Engine Load. Totally removable and doesn't require any modification to anything. It also allows the OBD cable to stay plugged in.

Looking good  . . .
You doo know how to put on a good display!
Roo b Roo
 

Am very impressed Kiteman - well done. Quite a tempting bit of kit - you thinking of going into business?

Not sure about going into business but don't mind making the odd one here and there if people want one.

In theory this should work on any vehicle that has an OBDII port

Kiteman said

Quote :

In theory this should work on any vehicle that has an OBDII port

That's interesting because it might allow calibration of the Engine Load (LD) readout numbers against the 'Current MPG' readout shown in our car.

osg

I would like one! I wonder if the info would make me drive more efficiently, and save some petrol costs! I take it the MPG readout is for water-cooled vans only, OSG?

Can't get MPG on either as I don't seem to be getting a reading for Mass Airflow, which is used in the calculation. Instead I've used engine load to give an indication. Should still be able to get RPM and engine load for air cooled,  coolant temp I think may be a problem

Many thanks to Kiteman for making this modified version that no longer interupts the starting of the engine.
Almost installed in the camper now. Still have a clamp on until the Velcro adhesive added to the Arduino unit is secure to the back of the RHS kickplate. Display fits well on the dash in the second row of holes from the windscreen. Just been out to buy black shrink wrap to tidy up/disguise the wires across the top of the dash. The power lead to the cigarette socket will hook securely over the steering column to keep it out of the way when not connected.
It boots up fine. All parameters show up well though I will have to learn what the LD (engine load) means by driving it along. Will have to wait for that until back on the road after winter.
Tried it first on the Citroen Pluriel but it didn't work there. Temperature showed a constant reading of minus 40C and both RPM and LD displayed zero. Perhaps the French have their own ideas for OBD output.

Brilliant job, Kiteman
osg

It's been a struggle but I now have MPG displayed  



Just need to calibrate it with fill up and distance data

kiteman wrote:

It's been a struggle but I now have MPG displayed  



Just need to calibrate it with fill up and distance data

Looks good. Where are the controls or rather how do you change the display?

There are no controls, they're the only two things I want displayed.

Shouldn't be too difficult to add buttons if I wanted, so I could scroll through readings, but as I said this is the only info I want at the moment

Nice work.

Another minor tweak

Coolant temp, average MPG and distance left in the tank.



For some reason the T from TEMP disappeared but that's fixed now.

Hopefully that's it now. 

That looks really trick now

Looking Good   

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Kiteman has updated my version of his OBD2 display to now show four parameters.

Three of these are read directly from the OBD2.
These are - TEMP (engine temperature), RPM and LD (engine load)

The fourth is MPG which is calculated from OBD2 readings of VSS (vehicle speed), RPM, MAP (absolute manifold pressure) and IAT (inlet air temperature converted to degrees Kelvin).

The MPG figures seem to be about what would be expected from road conditions and speed.
Keeping Engine Load below 25 returns a MPG figure of 35 or better.

osg wrote:

Keeping Engine Load below 25 returns a MPG figure of 35 or better.

Ha, have fun with that. I've noticed that 50% is where consumption really starts to take a hit.

Latest update.

All is not as I expected. The reading I'm getting back for tank level to workout miles left in tank doesn't change, it's staying on 7, even thought he gauge moves  Wondering if it's reading the small starter tank.

The MPG calculations are about 1.2MPG out at the moment, tweaked the code slightly and will see how it goes. On a 255 mile round trip managed 35.9MPG, that was with sitting in traffic for an hour and a half as well

Having the Coolant temp readings has really helped. Had an airlock in the system and seeing the temp fluctuate whilst driving was a good indication, doubt I would have noticed otherwise. I now know the fan kicks in at 103 degrees.

Now that the tank fillup reading doesn't work, need to find a 3rd thing to display now

I've noticed my fuel level reading doesn't change "up" after a fill but it does go down, as does the "miles to empty" reading. This has had me puzzled and I've concluded it's not a live reading but something computed.

Likewise, my mpg isn't as per odo reading & gallons used spreadsheet. However, I've put that down to wheel size differences from stock, as I notice the ECU thinks its going faster than it actually is (as logged by GPS) by a factor of about 10%. So, as well as accepting the fact that my odo is going to have more kms on it than actually travelled (and so I'm having to pay for services more frequently as well) I've about given up on the instant mpg reading. Its nice to see it from a "see how well in driving" perspective but as an accurate tool it's sort of meaningless when it doesn't tie in with the van's figures.

That said, I'm interested in having one of your kits. Will chat at the Sleepover.

I've adjusted my speed and milage in the code to account for my smaller wheels and tyres, so I should be getting pretty accurate figures

kiteman wrote:

I've adjusted my speed and milage in the code to account for my smaller wheels and tyres, so I should be getting pretty accurate figures

Your figures might be accurate but they won't tally with the odo, which is still set for original.

The reason I'm interested in the kit is I'd like a slightly more permanent display, one that fits in the gap to the right of the Speedo. Just getting a little fed up of the need to have an android phone stuck to the dash.

As the miles left in the tank didn't work, I've decided to stick with RPM as my third and final reading



Apart from any final tweaks to the MPG data I think I'm finally done

Kiteman said

Quote :

I've decided to stick with RPM as my third and final reading

In the version supplied to us by Kiteman we have a four reading display.
Engine temp MPG
RPM Engine Load

If keeping only 3 readings I would drop RPM and keep Engine Load.
RPM is not very useful
Engine Load is a better indicator for light-foot economy then MPG

Very pleased with our system.
osg