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My cousin is an electronics engineer and designs GPS tracking systems for truck companies. We were talking and i told him an idea i had...

Have one digital display to show a variety of different sensors like temp, voltage, pressure, dutycycle ect.

Have buttons to select what you wanted to view, and have predetermined thresholds for each input, and if they were exceeded, that value would display and an alarm would sound.

I thought of using it to monitor inputs like

Water temp
Intake temp
Exhaust temp
Boost pressure
Fuel pressure
Voltage
Current
Duty cycle
Knock


We were just gonna build one for me, but if there is enough interest, we could make a bunch of them

What are your thoughts?

Give us ideas, and we will see what we can come up with.

Sounds complicated but hasn't it been done before? I'm pretty sure you can buy digital gauges that monitor multiple parameters.
Have you seen the SubDataScan unit? No alarms but a wealth of information including injector pulse widths & intake air temps. Not made for the old EA82 though. The Wolf3D has a good display as well.

It has been done before, but i was thinking of making a little cheaper than the other off the shelf options. I cant think of the name of it, but it was over $200

Im aware of the Subscan, but i want something that can read EA82 sensors and be affordable to anyone.

Its only an idea at the moment, but i'll build one and see how i go.

It is based on a microcontroller, so it can be reprogrammed easily if you wanted to change something

Have a look into the digital PLX gauges.

That's what aircraft have had for quite a while. It was found that too many numbers counting up and down as things change was much too confusing for pilots, so in the end they went to digital screens displaying analogue gauges alongside hard numbers. With function buttons to change the page being displayed.


The aircraft I work on now has six displays, five of which are fixed (two ADIs, two HSIs, and an engine display. The sixth one can display electrical info, pneumatic/aircon info, hydraulics, additional engine info, a few fault display pages, fuel info, and perhaps one or two more things (can't remember off the top of my head).


It's doable in a car, of course, but I think the coppers would want you to at least have the speedo permanently displayed.

http://www.scangauge.com/

Mate runs one in his new gutlux twurbo diesel. Stuffed if I know why though.

i'd say its impossible to diy at a competive price to the commercial units for a generic device - considering the neat package built for them.

However for a single display, based on 7seg, leds for displaying one quantity prominently I don't think there is any commercial one out there, and you could make it cheap, I nearly completed one, to mount inside the dash (the pcb with the leds with ribbon wires to the uC pcb located elsewhere), but i don't have that car no more, so one of my unfinished projects now.

I was just looking at some links and wondered how they get MPG info, I mean I doubt cars have fuel metering devices, as you have to measure to and return flows, and those devices aren't cheap, so I think its derived based on injector timings, anybody know better?

I wasnt planning on replacing the speedo tacho part of the dash.

My idea was to mount it somewhere like you would any other gauge, but this one can display many inputs, and has alarms for its inputs

Scangauge is pretty much what im thinking of, but this will be compatible with the l series sensors.

Yes fuel usage can be calculated from injector output. If you have 250cc injectors in a 4cyl car, at 50% duty cycle (which might be 3500rpm flat foot) you should be using about 0.5L of fuel per minute.

its been done to death for newer cars but is still a cool project for the older cars. I have played with the early EJ stuff alot myself, havnt done anything ith EA engines though.

scangauge and the like get all their info from OBDII, but i recall seeing a few on the web that use analog inputs and tacho etc, with programmable calibration - that would suit the ea82 setup. So its been done to death also....
the most useful bit of kit is the wbo from techedge, very useful for self tuning the ea82t. hmm they have some nice new displays now.
And you can choose to diy kit some of their products:p
Well worth the $ too which is really not that bad for what it is.
Whats more, its got some additional spare A/D inputs and tacho input which you can hook up to tps,etc, and get timelined logging, with the wideband data. hmm not sure if i'm going to need it anymore....

dredge bump

I would hazzard a guess that this may be possible using a raspberry pi, or beagle board and arduino combo.
I have 2 raspberry pi's but i am not a coder, nor do i really have the time to learn atm.

I do know there are apps that connect to an OBD/OBD2 dongle via bluetooth available for smart phones. I don't think these would work with the computers older than the 1989 OBD subarus.

An open source scan program on a linux platform may be coaxed to work.

TOONGA

A good OBD scanner/reader is the UltraGauge

UltraGauge supports all OBDII protocols including:


J1850 VPM Early GM & Chrysler Ford Early Ford 9141 Early Chrysler and Foreign KWP 2000 Rare, various 11-bit CAN Most 2008 and newer 29-bit CAN Most 2008 and newer Honda & Volvo

My friend has a OBDII Bluetooth tool that sends lots of this type of info to his iPhone, then he has a screen display app that displays all this on his double din stereo screen

I've wanted to do something like this for a while.

http://forums.nasioc.com/forums/showthr ... ?t=2459432
http://hackaday.com/2013/01/29/adapting ... d-opening/
http://legacygt.com/forums/showthread.p ... ht=android
http://forum.liberty.asn.au/viewtopic.php?f=22&t=20123

A 7" cheap tablet with wifi/bluetooth wireless connection to OBD port mounted semi permanently into a dash. Plenty of free and cheap programs that can be set up with custom interfaces and the better ones have alarms.

I even bought the tablet and bluetooth OBD adaptor...