Auto Engine Instruments from R-Pi or Arduino

SCCutler

Administrator
Management Council Member
PoA Supporter
Joined
Feb 27, 2005
Messages
17,271
Location
Dallas
Display Name

Display name:
Spike Cutler
My 1976 Eldorado has no engine instruments, I have no interest in having a big, clunky gauge set ganging down from the dash, and I want to have some gauges. So, it seemed to me that, surely, someone must have programmed up an electronic gauge package using either Raspberry API or Arduino and some analog sensors - but darned if I can find any (besides some using OBD - II which, of course doesn't exist on a '76).

Suggestions?
 
I can't imagine how that would work, considering it's a vehicle with few electronic instruments to begin with. I'd guess you'd have to first install some sensors (voltage, water temp, oil pressure). Then you'd have to source a box to run those connections to which had Bluetooth support so that a phone could connect.

Sounds like a hassle. I'd just find a way to mount the usual 3-pack in an inconspicuous place (glove box) and move on. You could find a single multi-function gauge and do the same thing.


Sent from my iPhone using Tapatalk
 
It has run this many years without them and NOW you want to know what is going on under that enormous hood? :confused: o_O :eek:
 
Yeah '76 is going to be tough. Once you get to OBD-II age of vehicles, there's gadgets that can send all the vehicle data to a smartphone. But '76, most of that is just analog electronics that needs repaired or replaced to make it work.
 
I can't imagine how that would work, considering it's a vehicle with few electronic instruments to begin with. I'd guess you'd have to first install some sensors (voltage, water temp, oil pressure). Then you'd have to source a box to run those connections to which had Bluetooth support so that a phone could connect.

Sounds like a hassle. I'd just find a way to mount the usual 3-pack in an inconspicuous place (glove box) and move on. You could find a single multi-function gauge and do the same thing.


Sent from my iPhone using Tapatalk

It probably has sensors for engine vital signs, but I expect they are switches only and tied to dash warning lights.
 
Don't feel bad. My 2016 Mazda6 Is similar. No water temp, oil pressure, or oil temp.
Trying to figure out no to hack the infotainment to display this and more.
 
Don't feel bad. My 2016 Mazda6 Is similar. No water temp, oil pressure, or oil temp.
Trying to figure out no to hack the infotainment to display this and more.

Isn't a 2016 still under warranty?!
 
Wouldn't be that tough to do with an Arduino, an LCD shield, and the appropriate sensors. Years ago my wife and I had a '69 Bonneville convertible that had nothing but idiot lights. I added a gauge set, the under dash style you don't want, but the point is I put tees in for each sensor, so both the idiot light and the new gauge both worked.

Or if you want to spend a little more and not have to build it, you could buy one of the compact engine monitoring systems made for ultralights and experimentals.
 
I saw a video of a guy who did this for his gas gauge.
 
Apologies for ambiguity; I most certainly know I'll have to install appropriate analog sensors. Just Dan no longer find a gauge set that doesn't look like it was meant for the rice rocket with the fart-cannon exhaust.

Just figured someone had done it...
 
If it makes you feel any better, many modern cars/trucks don't actually show the data even WITH the gauges. As long as the computer isn't reading too low (oil pressure) or too high (coolant), the gauge is showing what the engine SHOULD be based upon RPM, throttle etc. basically an idiot light disguised as a gauge.
 
My 1976 Eldorado has no engine instruments, I have no interest in having a big, clunky gauge set ganging down from the dash, and I want to have some gauges. So, it seemed to me that, surely, someone must have programmed up an electronic gauge package using either Raspberry API or Arduino and some analog sensors - but darned if I can find any (besides some using OBD - II which, of course doesn't exist on a '76).

Suggestions?
SparkFun Electronics does almost all things Arduino and PI. More digital stuff than analog though. I'm sure their temperature stuff would work. The pressure stuff might need a bit of fiddling.

I was thinking about rolling my own home thermostats using their stuff. Might do it someday when remodeling so I can get the wiring right.
 
It probably has sensors for engine vital signs, but I expect they are switches only and tied to dash warning lights.
Right, they'd likely be set up as switches to trigger the idiot lights, rather than show a variable reading. Obviously it's fairly easy to install true temp sensors/oil pressure/voltage, but as far as mounting it out of sight, it's tough to do in a way that allows you any decent access to actually view them.

ATM-1414_xl.jpg
 
I remember years ago, back in the '70's, my dad had a '72 Suburban. He put a bigger gas tank in it, so the gauge was off and always read at least 3/4 full. Well, along came the gas crisis and you couldn't fill up unless it was reading less than 1/2, so he disengaged the gas gauge, drilled a hole in the lens and moved the needle, but he still needed a way to know how much gas was left, so he bought an electronic gauge that sat on top of the steering wheel (if I remember correctly). It had a bunch of monitors and a "high tech" digital (red L.E.D.) display. So, they did exist back then, but that probably doesn't help you now.

Edit:
Here is more helpful link to some resto mod stuff:
http://www.rodauthority.com/tech-st...lling-aftermarket-gauges-in-your-classic-car/
 
I remember years ago, back in the '70's, my dad had a '72 Suburban. He put a bigger gas tank in it, so the gauge was off and always read at least 3/4 full. Well, along came the gas crisis and you couldn't fill up unless it was reading less than 1/2, so he disengaged the gas gauge, drilled a hole in the lens and moved the needle, but he still needed a way to know how much gas was left, so he bought an electronic gauge that sat on top of the steering wheel (if I remember correctly). It had a bunch of monitors and a "high tech" digital (red L.E.D.) display. So, they did exist back then, but that probably doesn't help you now.

Edit:
Here is more helpful link to some resto mod stuff:
http://www.rodauthority.com/tech-st...lling-aftermarket-gauges-in-your-classic-car/
Damn, it sure would have been simpler to just install a fuel level sender appropriate to the larger fuel tank. They can be tuned with resistors if needed.

Some people do simple stuff the really hard way.

If you REALLY want gauges that actually tell you something, stick with the really old fashioned, mechanical, über-simple devices. Electrical temperature and pressure sensors tell you as much about your electrical system than they do temperature or pressure. And putting an arduino in the way? Now, you have a bunch of unnecessary unknown software in the loop. Lots of ways for other variables to creep in there.

And tees are fine for pressure sensors, but inappropriate for temperature. Temperature sensors must be immersed in the flowing fluid or they don't measure anything useful.
 
And tees are fine for pressure sensors, but inappropriate for temperature. Temperature sensors must be immersed in the flowing fluid or they don't measure anything useful.

It may not be optimum, the tee worked quite well for the temp sensor when I did it. A brass tee right on top of the engine block, with coolant flowing all around it it gave consistent readings, if it was off a few degrees it didn't matter.
 
I've done almost exactly this with a laptop running Labview (blech) and a TI DAC. Python works too.

It could probably be done with an Arduino pretty easily but not sure how to display the data. I suspect that for someone versed in app programming it would be pretty straightforward.
 
Don't feel bad. My 2016 Mazda6 Is similar. No water temp, oil pressure, or oil temp.
Trying to figure out no to hack the infotainment to display this and more.

Pretty easy to get a Bluetooth obd reader and there are plenty of apps to show vitals.

That said, I've got an older Mazda 3 and even at 160k I can't see why you'd worry about any of that stuff. Rock solid.
 
Pretty easy to get a Bluetooth obd reader and there are plenty of apps to show vitals.

That said, I've got an older Mazda 3 and even at 160k I can't see why you'd worry about any of that stuff. Rock solid.

I like having the gauges available rather than an idiot light. Case in point: a month or two ago, I was driving the wife's truck (I rarely do) and the oil pressure was dropping down to zero. There was a message about low oil pressure that was displayed and a faint chime, but I couldn't hear the alert chime (radio on at soft volume, no windows down). What I noticed was the instrument reading, not the system display. Turns out she had been driving with low oil longer than she should have because she had been trying to make time to get the oil changed. I turned around and drove the few miles home, changed the oil myself, and everything was right as rain.

Unfortunately, many car makers have turned gauges into idiot lights by making them only read "normal" unless there's a problem outside the specified range.
 
Back
Top