0-100psi fuel sending unit connection

[blownbluez06]

I searched for answers on this thoroughly and came up with a 0.
I am wondering if anyone is using just the Kavlico or autometer 2246 raw sending unit with the pigtail and logging it with the EIO. I am interested in doing that, but the input is 5v. I know I can tap any of the many 5v sensors to get my 5v, but the data sheet mentions the max draw for the sensor is 5 amps and I am concerned with interfering with the 5v bus from the PCM or any of the sensors outputs. I sent an email to Kavlico for clarification to see if the current draw is based on the output impedance. If it is, then I will be fine. If not, I need to hear from you guys to know what you're doing for this.
Here's the data sheet. Autometer uses Klavico sensors.
http://www.kavlico.com/_assets/pdf/P255DS.pdf

I will post up the answers from kavlico

[blownbluez06]

Here is Autometer's response.

"You are correct in not wanting to tap onto an existing PCM reference circuit. There can certainly be negative ramifications loading down a 5v circuit like that. I would recommend using a regulator like a Radio Shack 276-1770. This will provide you the proper reference voltage for the sender."

http://www.bek.no/~flemming/flemmweb...inear/7805.pdf

[mr.prick]

You can get 5v from the PCM itself.
What PCM are you using?
LS1 Fuel Pressure Sending Unit Tutorial

[blownbluez06]

That's great! That's what I need. Thanks Prick!

I have a 2002 Z06. I'll have to find where to get the pins for pinning the PCM plug to use the EGR I guess. It would be better than having more wires in my EIO plug.

[blownbluez06]

Just an update for those that may need this information:
Got the pins, wiring and plug all assembled to suit my desired length from EFIconnection.com. Sensor ordered from the popular auction site. All will be going in the car this week.

[robert56]

Are you still going to a complete How-To, with pictures and all that? I would be more than happy to host it on my web site with my other tuning stuff, and of course you would get credit and be copyrighted with proper disclaimers. I too plan on adding this to my Z06, as soon as your done, lol.

So what your saying is using the Autometer sender won't work directly into the HPT EIO because it has an amp draw that is too great? Seems that adding the Radio Shack regulator may be easier overall, just speculating based on locating and digging out wiring/pins on other jobs?
Thanks
Robert

[blownbluez06]

Hey Robert. I'm the same name in CF, so I feel like I know you. LOL
Your website's great. That link from Mr. Prick is actually pretty good. I did a small writeup in CF C5_F/I section. I got going and didn't get many pics. If you quote me on that CF thread, you can download those pics from my family server and you're welcome to them. I decided to grab the voltage and ground from the PCM and got a plug with 3 pre-cut and pinned wires from eficonnection.com. I hid my sensor by the alky pump behind the driver wheel and it took every bit of the 8ft length I ordered. If you're going off the fuel rail, I would recommend 7ft to be safe, but think 6.5 would suffice. The 7805 regulator can be used as well. Radio shack's part # is 276-1770. Those clowns up there didn't know what I was talking about, so I just went to their drawers of components for what I needed. It was around 2 bucks and can supply 1 amp. Kavlico's engineering drawing shows that sensor draws 5amps (max) (see here: http://www.kavlico.com/_assets/pdf/P255DS.pdf ). That didn't mean much. Autometer told me that thing only draws .5 amps at the max. Makes more sense to me. Best place for the sensor that I could find was on the popular auction site. I got mine for 89.00. Feel free to PM me for my e-mail if you'd like to discuss this any further.

[KFZ)^]

Good work, blownbluez06.

...adding this to the To-Do List.

Cheers!

[Fast9C1]

Kavlico's engineering drawing shows that sensor draws 5amps (max) (see here: http://www.kavlico.com/_assets/pdf/P255DS.pdf ). That didn't mean much. Autometer told me that thing only draws .5 amps at the max.

Not sure where you saw 5A. The spec I see is 5mA, which is milliamps, or .005 amps. THAT seems even more plausable than a half amp to me.

EDIT: Now this looks much more useful to me with my manifold referenced regulator:
http://www.kavlico.com/catalog/fuel_rail.php

Can't find a spec sheet on it, but emailed asking for more info.

[blownbluez06]

On the link I posted, it does read 5ma. But the engineering sheet I was looking at, I could swear it read 5A and not mA. May be just a momentary lapse of reason.
One other thing. The engineering drawing reads .5v@ 0psi to 4.5v @ full pressure. Keep that in mind when you're scaling it. I am only assuming that Autometers' sensor is the P255 though.

[Fast9C1]

Figure I will just keep posting in this thread. No word back from Kavlico yet (attempt #3) on that differential pressure sensor which appears perfect, but is most likely quite expensive.

Not having any recent firsthand experience with anything other than my Tahoe/LeSabre/Caprice, I can only poke around and search. This particular quote leads me to believe that there are possibly millions of useful sensors deployed in OE applications that would work:
http://www.stangnet.com/mustang-foru...ml#post7942714

Your car doesn't have a fuel pressure regulator. The sensor on the fuel rail is a manifold-referenced pressure transducer that tells the PCM what the pressure in the rail is with respect to the manifold pressure. The PCM uses that sensor to adjust the output duty cycle of the FPDM (fuel pump driver module) which drives the fuel pump in the tank. A higher duty cycle means higher fuel pump speed and output meaning more pressure. Lower duty cycle slows the pump down and output and pressure drop. So the "regulator" in these "returnless" fuel system cars is really a closed-loop control system consisting of the PCM and FPDM with feedback from the pressure sensor.

That thread was about fuel pressure on a 99 Mustang GT. Finding info on that particular sensor hasn't been easy (motorcraft, rock auto, etc). Anyone know off the top of their head how these Ford sensors work?

The requirement is pretty straightforward: 0-5v differential fuel pressure transducer. If this doesn't pan out, it looks like writing my own custom PID equation will be in order.

[PitchblackC3]

I was looking at getting one of the autometer 0-100 psi sending units and wiring it through my EGR plug since it is close and I have eliminated the EGR. It looks to me like the sending unit uses the same plug as the 99-02 truck TPS. Is this true? If so I'm not gonna waste money on the harness to go with the sending unit.

[blownbluez06]

Yes. That is correct. You can use the TPS. For me, it was just worth the ~15.00 to have a new, clean harness with the length wires I needed to reach the PCM and with pins to plug right in to it. Also to save myself from having to spend the gas and time to go cut one out of a car at a junk yard.

[PitchblackC3]

Well I have several harnesses in my shop I can just grab one off of.

Thanks for the info!

[KENS80V]

I'm going to use a TPS plug as well for the Autometer sender. Can someone tell me the pin out arrangement for the autometer plug. The connector is marked "A B C". The three wires on the autometer pigtail are Red, Black and Purple.

[mr.prick]

Autometer 2246
"A" = (ground)
"B" = (5v reference)
"C" = (return signal from sender)

[PitchblackC3]

Awesome info, this is gonna make my install a snap. Well about three splices and then a snap..ha

[KENS80V]

Can you also help with the creating the custom PID and formula in HP Tuners?

[mr.prick]

The Autometer 2246 sender has a range of 0v-4.5v
(Volts*25)-12.5 = PSI
(Volts*25)-12.5)*6.894757293168361 = kPa

[PitchblackC3]

The Autometer 2246 sender has a range of 0v-4.5v
(Volts*25)-12.5 = PSI
(Volts*25)-12.5)*6.894757293168361 = kPa

Isn't that formula for 0.5v - 4.5v ?