Fuel Tank Level Gauge

[BoyRacer0013]

I am wanting to add a fully digital dashboard to my car using Tuner Studio. However, I cant figure out how to display the level of fuel in my tank. Do I need some type of I/O board? If so how do I interface it with Tuner Studio?

More information on my project can be found on the Mp3car forums here:
http://www.mp3car.com/newbie/149653-new-to-this-forum-lotus-project.html

[LT401Vette]

You will need to be using a firmware that passes the voltage of an input pin or IO board back to TunerStudio in the runtime data.
What firmware and MS version do you have?

[BoyRacer0013]

You will need to be using a firmware that passes the voltage of an input pin or IO board back to TunerStudio in the runtime data.

So I the sensor will hook to the MS, and send its output to TunerStudio the same way any other sensor would?

What firmware and MS version do you have?

I don't, I want to make sure I know what I need when I do get a MS.

[BoyRacer0013]

I know this seems to be kind of a "noob" question but how are the gauges driven when a MS is the only ECU in the car?

[jsmcortina]

I know this seems to be kind of a "noob" question but how are the gauges driven when a MS is the only ECU in the car?

It depends on how they were driven before. Mine are all independant. I'm guessing you are saying that yours are not. In that case you might need to retain the original ECU just to run the gauges or replace the gauges?

James

[BoyRacer0013]

What do you mean by "independant"? I am planning on replacing all my gauges. The only gauges I need to run are speed, rpm, and fuel. What is the best way to run these gauges?

[LT401Vette]

What do you mean by "independant"?

Gauges that don't require your cars ECU, so they work even if you take stock ECU out of the picture.
All gauges used to be independent, then some of them became more of a readout of the ECU's information.
Some modern cars have many/most gauges that read out ECU values more than directly from the sensors.

I am planning on replacing all my gauges. The only gauges I need to run are speed, rpm, and fuel. What is the best way to run these gauges?

This is up to you..
But you can easily run all of those independent of the stock ECU.
RPM can use an MS Tachout
Speed can use an MS3 VSS out, or if you have the right converter you can go direct, this is assuming you have a VSS in the car.
Fuel I would go direct against the sensor unless you have some reason you want to see the value in TS.

[BoyRacer0013]

... even if you take stock ECU out of the picture.

My car is gonna be a bit of a hybrid of the old and new (mostly new) I have no plans to use a stock ECU, I intend to buy a "drop-in" engine for a Ford Focus ( dose not come with ECU )

All gauges used to be independent, then some of them became more of a readout of the ECU's information.
Some modern cars have many/most gauges that read out ECU values more than directly from the sensors.

Is there some advantage to reading values from an ECU as apposed to direct from a sensor?

Speed can use an MS3 VSS out, or if you have the right converter you can go direct, this is assuming you have a VSS in the car.
Fuel I would go direct against the sensor unless you have some reason you want to see the value in TS.

This is where I'm confused, is a VSS independent of the rest of the computer system? How dose a VSS work? Will I need to get a MS3 or can I do with a cheaper version of the MS?

[LT401Vette]

This is where I'm confused, is a VSS independent of the rest of the computer system? How dose a VSS work? Will I need to get a MS3 or can I do with a cheaper version of the MS?

Older cars had a gear driven cable that drove the speedometer directly, most modern cars use a VSS. A VSS just puts out X pulses per mile, so something needs to decode that. Typically your Speedometer does, but it will be fixed on a specific pulse per mile ratio. The PPM will vary with make and model, then if you do any gearing changes it will change again, so you will need some way to correct it to the speedometers expectations. With an MS solution, MS3 is the easiest option. But there are other ways, other correction decoders or after market speedometers that can adjust and don't need to go through your MS. Another advantage to having the MS do it is that it is that you can then datalog your speed and use it in other ways.

In most cases I see little reason reason to want to run fuel level through your MS, it is important for you to know you need to get to a gas station, but not very interesting data in a log.

[aarc240]

Have a look at this site:
http://www.speco.com.au/gauges.html
These are what would be termed "independent" gauges but in the case of speedo and tacho could also be configured to be driven by either the sensor inputs to the ECU (eg MS3) or from the ECU itself.
Under the speedo section, have a look at the installation guide, it gives clues to how it might be set up in almost any car.
I'm using both speedo and tacho from these people and have them configured "a bit of both" in that the tacho is driven by the MS3 (so it's an ECU controlled gauge) and the speedo uses the VSS input from a front wheel (RWD car) after the VR sensor interface to a jbperf I/O-x board (so it's a semi-independent gauge).
The speedo could equally be used with just a VR sensor on a hub or the driveshaft which is then conditioned to suit the gauge by a jbperf VR interface board, no ECU needed.

Phil is correct in that there is little sense in a fuel gauge input into an ECU. Logging the pulse rate and duration or more usefully a computed fuel usage rate does make sense but even then only if you have either a VSS input to turn it into usage per kilometre (or mile) or use a time relationship to give something like pounds per hour.
About the only practical use I've seen for logged fuel tank contents has been in fleet vehicles where it can be used to detect employee theft.

[BoyRacer0013]

Okay, I understand that in most cases having a fuel level sensor hooked to a MS is pretty much useless. The reason I want to do it is because I want to run a full digital dash with a fuel gauge, as well as being able to remotely check things like fuel level, temps, speed, ext. to do this I will run a full computer in the car, with TunerStudio and media apps. But I would like to also run the three standard gauges for some redundancy, they will not be my primary displays.

[aarc240]

In that case have a good look at the I/O Extender on jbperf.com and related posts on http://forum.jbperf.com/index.php.
While the MS3 / MS3X has a good capacity to do stuff barely even dreamed of 10 years ago, it really isn't the place to be doing some of those things.
Instead of loading up that processor and it's i/o with tasks other than running your engine to it's best advantage, shift the load onto another device which TunerStudio is well able to use and has the capacity both in processing power and i/o to do just about anything within reason.
You can likely do much of what you want with the MSgpio also but I can't comment on how user friendly that may or may not turn out.

[BoyRacer0013]

Okay, it makes sense not to load a MS with things other than running the engine. I was thinking about running some type of logic board as well, to control things like the lights and wipers. I want to have control of the logic board via the computer as well as the standard switches on the dash. Are these I/O boards capable of this function?