I need a technical description of "FUEL FLOW RATE" pin 43 on PCM

[98formulaLS1]

I need a technical description of pin 43 on the PCM. Its called FUEL FLOW RATE. I have determined that not all PCMs have this signal enabled. I am 100% sure that the 5.0's, and the 4.0 SOHC have it. The 4.0 OHV doesn't have them. I may just be a few, or it may be all of them, not sure yet.

If anyone can derive a technical description of this signal, please inform me. I'm an electrical engineer, so please be a technically precise a possible.

thanks in advance.

 

[scucci]

Maybe not much help. The schematic shows it as fuel flow signal to the electronic message center used for fuel range/mileage calculations. TS guide shows 12 Volt at key on dropping to 2 volt at idle. It does not get specific about the signal or if it is pwm or just analog. It is used on vehicles that have the message center option. If I had one I'd put a scope on it and let you know.

Good luck
Scucci

 

[98formulaLS1]

thanks.

I have found out that not all 4.0L OHV have the PCM with the FFR enabled. I would be interested to know if any Eddie Bauer editions came with a 4.0 OHV. If so, I would buy a PCM from that car. Right now, with the Message Center connected to what should have been the FFR signal, The message center shows that my Instant Gas Mileage goes from 0, to 50, to 75, then to 0, and thats only if I have the A/C on. oh well.

If someone put a scope on it, and gave me a technical description of how the FFR could have been calculated, I can design my own interface for it.

 

[boominXplorer]

Does the accumltive gas mileage work at all? In my 00 I only have accumulative and not instant gas mileage. Might be able to run a newer message center, but I am sure something else would be different to put you in another snag.

 

[98formulaLS1]

Does the accumltive gas mileage work at all? In my 00 I only have accumulative and not instant gas mileage. Might be able to run a newer message center, but I am sure something else would be different to put you in another snag.

you know what, maybe since this message center is from a 1998 EB, the FFR signal is different than the one coming from my 2000 X.

Why don't we meet up for a little bit, let me plug your Message Center into my car and see if it works. Do you have any objections to that?

I'll PM you my cell.

Thanks,

Dan

 

[falcaraz]

I just finished installing a message center in my exp too and i seem to have the same problems. My MC is from a 97-98 exp i believe and i cant get the fuel mileage to work. the only thing that seems to work is the gallons used feature. I was looking thru the install guide (http://www.explorerforum.com/forums/showthread.php?t=80670&highlight=message+center+install) and saw that it says to ground pin number 32. But on the service cd it says that wire is for engine select and grounded is v8, open is v6. Could that have something to do with this?

 

[98formulaLS1]

I have spent MANY MANY hours researching this.

1. Do you have a 4.0 OHV? I would assume so if you are having this problem.
2. If so, you leave pic 32 disconnected. Open means that you dont connect it to anything.
3. I have some very valuable data that you might want to see regrading this install. I've complied a very detail spreadsheet just for this specific install.
4. If you do in fact have the 4.0 OHV, then our only option to make this message center console work is to obtain a ECM from the 1996 Eddie Bauer Explorer. This seems to be the only year that I can find where the Eddie's use the 4.0 OHV and the message center. This means that during this year, Ford enable the fuel flow signal output, while disabling it in other years.

Shoot me a PM with your email address and I can send you all the data I have on this install.

That install page you used is kinda hard to understand. I think I'm going to make an new awesome DIY thread for this topic just to set the record straight.