mikeborden

DUDE! Are you a computer nerd?

That's quite awesome though!


Mike

Ahsai

Haha, no, I didn't even know what Ardunio is a few wks ago! It only looks complicated but the principles are very simple.

It's a lot of work for this mod but half of the fun is the process of learning and creating Hope someone will also enjoy it like I did.

phil996cab99

I'm a software guy, so I'm digging that aspect of it.

If you ever need to add moving averages, regression to the mean, etc. hit me up, but I'm guessing you'd have no problem w/that.

alpine003

There's quite a bit of different API's available for the Arduino boards. The last one I did for a friend that tied in his universal TV remote to an Arduino to control a motor allowing him to rotate and tilt his tv stand. That one was all done in JavaScript programming.

It's all really just inputs and outputs. Sense an input and program some logic on what output you want to send a voltage or signal based on certain criteria's.

philooo

I really hope someone pick that data and build something ready to install.
I may try the DIY way but I'll have to wait for the fully documented DYI as I know nothing on electronics

Ahsai

Yes, it's quite simple once you know what it's doing. Actually more design is needed on the analog circuits surrounding the micro-controller.

I tried to use just a simple opamp and implement the mapping using analog but the calibration is a nightmare and it's not accurate either. So mc is the way to go with its flexibility to be re-programmed and re-calibrated when newer data points (225F+) are available.

Phil, I knew you've been asking and waiting for this forever. Will let you know if I ever develop it further to something more readily installed. As is, it does require some electronics knowledge unfortunately.

philooo

You are our only hope

5CHN3LL

Don't know how I missed this thread - I've been looking for something to do with my old 'Duino since I started playing with the Pi. I think I might go with an Adafruit LCD display instead of the gauge, but what an awesome hack. I love it.

Ahsai

Thanks! Digital LCD display will be even easier. All you need is the first temperature vs voltage function in post #15.

I never get around to complete mounting the gauge but I researched quite a bit and finally found a stock looking gauge panel to fit the CD holder rack perfectly (single DIN) $20 here http://www.ngpracing.com/newstore/42...olf-jetta.html

It's very well made and the texture matches very well with the console. You will need some creative way to mount it (maybe use some springs) and also decide what to put in as the second gauge but I think it will look quite nice when finished.

Schnell Gelb

The usual Ahsai brilliance !
Well done Ahsai -you've added more useful,usable tech to the 996/M96 subject than most of us combined.This is just your latest.
A prior Post asked about fitting an old school oil gauge.
There is a convenient port on the cam cover.It is sometimes used by the IMS lube line kits. a.k.a. DOF.This could be used for a sensor or a simple oil line direct to a gauge ?
This could be just a diagnostic connection.No need to run the oil line or wiring to the cab .

Ahsai

Thanks Schnell! I'm aware of that port but the drawback is it's at the end of an oil gallery so it's only good for sensing oil pressure and the oil flow there is not optimal.

The beauty of this hack is it's using the stock oil sensor which sits in the sump, which sees the HOT oil dripping from the main bearings first hand.

With this gauge, you can see the oil climbs up almost instantly when you race up a grade while the coolant temp gauge doesn't move at all (until much later when you slow down the car). I guarantee a quick response of the gauge to your right foot

ChicagoSpeed996

Fantastic mod!! In the 997 they nixed the voltmeter and replaced it with an oil temp gauge. This is a great tool! Nice work!

sjg1138

From an ex-embedded software engineer, this is awesome!

Ahsai

Thanks, guys! Must be like a child's play for you then, Steve

I just wish it's a bit easier to put together for an average DIYer. This is the best I could come up with w/o hacking into the Durametric way of retrieving data from the DME.

BTW, since the hack I've discovered Porsche's documentation on the stock oil temp sensor temp vs resistance (R2) graph and from that, I was able to compute/derive the value of the internal resistor in the DME - 8k ohm (R1). The implication is with the temp vs R2 graph and known value of R1, we don't need Durametric for calibration at all and we can access the full range of oil temp without real oil temp measurements (which is difficult to produce unless you drive on a race track or you remove the sensor and dip it in very hot oil )

I drew a circuit diagram like this.

knfeparty

Sorry if I missed this, but how did you identify which plug and pin went to the temperature sensor?

I still want to do this mod to my 996, but more so I want to add a transmission temperature gauge on my cayenne for towing. So, I'll need to figure out the right pin for it, since it also has a built-in temp sender that the durametric can read.