System to readout dual flow sensors

[racprops]

I have read just about every post and link to other posts on this subject.

And I can see it is a few old threads.

Perhaps I can get some interest and some help??

I think some of the suggested flow meters will work or I will see about making a multivane pattle wheel version, that way to get the most pauses per second of slow.

BUT a major problem remains for us working on Fuel Injected cars.

Current tech is devices like Scan Gauge II which work off the cars computer and thus is unable to show real MPG changes unless the cars computer "sees" them.

I have a couple of old Zemco Mileage Computers which work off a fuel flow sensor and off a sensor that works on the drive shaft to get speed. The computer all ready compares speed and distance with fuel flow to calculate MPG, miles traveled etc.

Problem is with my 2000 Ford Fuel injection there is a return line returning fuel to the tank.

So my flow sensor will "count" all flow, to the engine and back to the tank. This will not work and what is returned to the tank will change due what the engine uses.

My solution is to run two flow sensors and then compare the two counts and then output the difference. ( now that I have read all of this thread I am censured about the flow sensors..)

I think it will take a small computer chip to sample say ½ a second of both signals and then output the difference, so it will be ½ second behind. No problem.

The output pauses are from a Photocell driven by a light bulb, the light is interrupted by a ball bearing running around a track so that once in ever revolution it blocks the light from the Photocell. I would really like to improve this with LEDs.

The output and thus input to the Zemco computer has to be a negative signal to ground.

Rich


PS or putting it another way someone said:

Old cars with carbs only need 1 flowmeter. newer cars and diesels will need 2 with a little converter box to subtract return line pulses from the fuel supply pulses. The converter box would run the calculated pulses to the MPGuino. MPGuino already has some very talented programmers who I am positive would have NO trouble whatsoever converting the software to figure the pulses per gallon. The cool part would be that you should only need one number for all vehicles.