Logging Fuel pressure with AEM 0-5V output

[tording99z28]

Can anybody tell me how to setup the PID in HPtuners for logging fuel pressure from an AEM fuel pressure gauge with the 0-5V output? I see the autometer PID in hptuners already but none for AEM. Will the autometer one work?

[LSxpwrdZ]

You will probably have to use a custom PID with a correct transfer function. You'll need what PSI range the sensor reads and at what voltage output for those readings to generate a transfer function.

[LilJayV10]

I am using an Autometer gauge and was wondering the same thing. Where would someone find out that information? I am assuming contact the manufacturer.

[DSteck]

For Autometer:

V/0.04 - 12.5


Not sure what range the AEM is. Find out and I'll give you the transfer function.

[tording99z28]

Just for kicks I loaded up the Autometer PID and it seems to be right on with the readout on the gauge inside the cab. It is a digital gauge and the FP is fairly steady so pretty easy to compare the two in real time. Should I just roll with this or not?

[edcmat-l1]

Could be the same sending unit.

Edit: I found a picture of it, and it does not look like the same sender. The gauge is 0-100 psi, not sure if that is the exact operating params of the sender though, could not find that info in a quick search. It is 0-5v though.

You could always rig up a pressure reg, and do a 0-100 psi voltage check.

[DSteck]

Fuel pressure sensors are almost exclusively 0.5-4.5v operating range (but still get categorized as 0-5v since they operate in that range). The AEM probably uses 0-100 as well. The only other common sending unit is 0-150psi. That one also uses 0.5-4.5v readable range.

[LSxpwrdZ]

I know the resolution wouldn't be that great because it is a much higher pressure sensor but has anyone tried using an old A/C pressure sensor as a fuel pressure sensor? I've been wanting to try it for a long time and just have never gotten around to it. I have the transfer for a stock A/C sensor as well.

[DSteck]

Fuel might damage the sensing element.

That's pure speculation.

[LSxpwrdZ]

Well I have a few spares and pigtails so I am going to give this a try.. I'll report my findings. Old junkyard A/C pressure sensors will be cheap to get and alot cheaper than the AEM or Autometer sensors.

I just wonder if it'll hold up to freon if gas will be that much worse??? Guess we'll see.

[pontisteve]

My AEM fuel pressure sensor is the 0-100 PSI one, and the analog formula for it is:

(V*25)-12.5

The inverse of that is (V/.04) - 12.5. So they are the same.

[Scourage]

Exactly what I was looking for in my search, except I didn't notice the - at first. Kind of threw me off as I was using + 'doh.

[redmonaro]

I use an ls1 oil pressure sensor, works perfect for me, i made an extension harness to plug into the engine harness and made up some adaptors to connect it to the fuel line, then just go into scanner and pick engine oil pressure abd log away

[RonSSnova]

This makes perfect sense! Nice job. I was thinking the same except I'll have to add those wires to my harness. The 99 Camaro just had a gauge, the PCM didn't know oil pressure.
Ron

[fullthrottle]

Well I have a few spares and pigtails so I am going to give this a try.. I'll report my findings. Old junkyard A/C pressure sensors will be cheap to get and alot cheaper than the AEM or Autometer sensors.

I just wonder if it'll hold up to freon if gas will be that much worse??? Guess we'll see.

Whatever happen with this James?

[LSxpwrdZ]

Whatever happen with this James?

Never ended up doing it with all the other projects that took priority over it. However I did find the transfer function for the Fbody AC pressure sensor. I'll just have to dig it up.

[bk2life]

Never ended up doing it with all the other projects that took priority over it. However I did find the transfer function for the Fbody AC pressure sensor. I'll just have to dig it up.

been 7 years... ever get a round to doing it?