MPGunio and flow sensor

[racprops]

OK I got my high pressure flow sensors in today.

Back in the 80s I bought a number of the great Zemco Travel Computers, they read out MPH, MPG and MTE (Miles to Empty) and a couple of other read outs.

These were made to run on the old carbureted engines and did their work by two inputs, a speed sensor made by putting four magnets on your drive shaft and placing a pickup coil close to the drive shaft and magnets, and by a flow sensor which read flow by sending a BB around a tract that cut the light from a light bulb and a photo sensor, both readings gave a pulse signal that depended on the speed of the spinning drive shaft (An early VSS) and how often the BB cut the light.

Now a days many cars include MPG readouts and all cars newer than 1996 had OBDII Ports and there are a number of aftermarket plugins that can provide TONs of data like MPG, GPH (gallons per hour) RPM, engine temp, ETC. Funny but oil pressure is on NONE of them…odd.

But these do NOT work on Fuel injected cars made before 1996. So cars and trucks made before these are the only way to add the MPG features…even OBDI system do not have any such device.

BUT there is a slight problem, fuel injection runs a higher fuel pressure that the 4 to 6 PSI of carb engines, and I fear the old flow sensor might leak.

So thanks to a great web site https://ecomodder.com/forum/ someone found these: https://www.futurlec.com/sensor/flowfuel30l0.shtml I ordered four of them.

And on a thread about them even found a way to double the output which should now read twice as fine readout: The normal specs:

Part Code: FLOWFUEL30L0

Features
• Flow Rate 2.0 - 30.0 liter/hr (Double output should run1.0 to perhaps 60. Liter/hr I am more interested in the lower flow readings.)
•
• Digital Output
• Fitting for 3/8" Barb
• Suitable for both Diesel and Gasoline
• Open Collector Output
• Fluid Temperature: 0 to 60°C
• Fluid Pressure: up to 85 psi (Will handle most nondirect Fuel Injections.)
• Supply Voltage: 2.4 - 26V

So first I want to use this MPG gauge on my 1993 Chevy Van which is fuel injected but OBDI system.

I also want to use one on my 2003 Ford Crown Vic as I am planning on doing work on it to improve its MPG. And I have found that the devices that run off the cars OBDII Ports is dependent on what the computer thinks is going on…and found if I fool it I also fool the readouts.

Now there is a grate MPG gauge system call the MPGunio found on https://ecomodder.com/forum/ and it does not run off the computer, but it currently runs off the injectors duty cycle and the cars VSS, as I think an idea to change the MPG will to be messing with the injectors I think I might mess up its readings.

There is the possibility it can be made to run off one of these flow sensors as well which than might be better lacking only one trick the old ENCO MPG computer has, that being MTE Miles to Empty.

As I am also posting this here has any one hooked a MPGunio to one of these flow sensors??

A feature that works by being told of a full up and them calculates gallons used FROM the known (told how much fuel the tank holds) total gallons in the tank.

On long road trips I found this helpful, especially during the last gas crash, if my planed gas station was close and the next x miles to go I could see that is a couple of cases I would NOT make it at my current rate of speed but IF I slowed to a better MPG speed I would…

So it can be a nice feature to have on a long road trip.

[racprops]

PS there was a great tread here about these flow sensors, can some one point me to it??

Thanks.

Rich

[Stubby79]

Question...where does this device install? On the pressurized fuel line?

If so...what about the fuel pressure regulator and the fuel return line? Won't it be measuring all the fuel passing through, including that which gets returned to the tank?

[racprops]

Originally Posted by Stubby79

Question...where does this device install? On the pressurized fuel line?

If so...what about the fuel pressure regulator and the fuel return line? Won't it be measuring all the fuel passing through, including that which gets returned to the tank?

There are two answers to your question:

First, with system with return lines you can add an aftermarket fuel regulator at the point of the TBI or Fuel Rails, connecting the return line there and leaving a single fuel line to supply the TBI (in my case on my Van’s engine) or at the fuel rail on say a pre 03 Crown Vic. I did this set up with my 93 Chevy van.

Second with many post 02 cars the fuel systems have switched to single fuel lines placing the fuel return lines at the fuel pump within the fuel tank, so there is no return lies at the engine.

So in both cases we now can have a single final fuel line at the final fuel delivery system where we can place the flow sensor with the added bonus of now having an adjustable fuel regulator.

The main reason for the fuel return line was to allow the fuel pump to run 100% of the time to insure gap-less fuel delivery and to cool the pump. This also help prevent a old problem of vapor locking common to the old fuel system.

But the EPA found this set up was warming up the fuel as it was recycled from the hot engine back to the fuel tank, this warming cause more vapor which cause more vapor leakage and more pollution, so it was demanded this was to be stopped, so dropping the fuel with in the gas tank allowed the fuel pump 100% duty cycles and kept the fuel with in the tank so it is not warmed up by being run past the hot engine.

Rich

[TheTestPilot]

Yes this sensor works with mpguino ,although a 10k ohm resistor
needs to go across the +12 power wire and output wire,1/4 watt is fine..
Provided you are feeding the flow sensor 12 volts the output wire then goes directlly to the mpguino injector input .
This mod creates a square wave output.
The sensor may need a 100nF capacitor across the output wire and ground wire if you have a noisy electrical system ,ceramic style at 50 volts will work fine.
Tp

[racprops]

Many thanks for this info.

Rich

Originally Posted by TheTestPilot

Yes this sensor works with mpguino ,although a 10k ohm resistor
needs to go across the +12 power wire and output wire,1/4 watt is fine..
Provided you are feeding the flow sensor 12 volts the output wire then goes directlly to the mpguino injector input .
This mod creates a square wave output.
The sensor may need a 100nF capacitor across the output wire and ground wire if you have a noisy electrical system ,ceramic style at 50 volts will work fine.
Tp

[racprops]

One problem is with all the things I will be running on my 383 SBC having a system that does not run off the Vans PCM and reads purely by fuel used and the vans speed will give the most accurate readings regardless of any things I change computer wise.

The other things like accurate speed and miles to empty etc. are nice extras.

As up until now the kind of readouts your can get for OBDII was not made for OBDi systems.

Rich

[racprops]

So I will answer these questions again in greater detail.

There are two answers to your question:

First, YOU MAKE a TWO line system into ONE line right at the injectors fuel rail,

With a two line system (One being the return line) system with return lines you can add an aftermarket fuel regulator at the point of the TBI or Fuel Rails, connecting the return line there and leaving a single fuel line long enough to put the fuel flow sensors between the new fuel pressure regulator then hook up a line from the flow sensor to supply the TBI (in my case on my Van’s engine) or at the fuel rail on say a pre 03 Crown Vic. I did this set up with my 93 Chevy van.

When I install my new 383 it will be running a Tune Port intake, same problem.

Second with many post 02 cars the fuel systems have switched to single fuel lines placing the fuel return lines at the fuel pump within the fuel tank, so there is no return lies at the engine.

So in both cases we now can have a single final fuel line at the final fuel delivery system where we can place the flow sensor with the added bonus of now having an adjustable fuel regulator.

Rich