MAP Sensors

[Roy]

Hopefully someone can help me out with an answer, Ustasa, Steve-SST, Sydneykid, Doughboy or any other person that may know.

On an R32 GTST there is a MAP sensor located on the firewall on the drivers side. This feeds the electronic boost gauge located on the dash. Now in ANY way does the std ecu, (and in turn a PFc) use this signal for ANY reason?

Secondly would anyone know what the range is, 1 bar, 2.5 bar.... i assume 0-5V.

Moving on from that question i also have an AVCR, which also uses its own MAP sensor. (From memory it is rated at 2.5bar, 0-5V) Now this signal is obviosly used by the controller to pulse the solenoid valve. So if i spliced into the signal wire that converts the pressure into a voltage and sends a signal to the controller, is a possible change in impedence etc going to cause any problems with either the 0-5V signal required by the AVCR, or secondly the quality of the analogue output i need.

Basically i need a 0-5V analogue output for vacuum and boost pressure, and im wondering if i can use either of the above MAP sensors currently on my car rather then buying a 3rd MAP sesnor.

Thanks in advance

[Sydneykid]

On an R32 GTST there is a MAP sensor located on the firewall on the drivers side. This feeds the electronic boost gauge located on the dash. Now in ANY way does the std ecu, (and in turn a PFc) use this signal for ANY reason?  

Yes, it is the pressure sensor for input to the boost correction table. Both the standard ECU and a Power FC use it.

Would anyone know what the range is, 1 bar, 2.5 bar

I understand it is both vacuum and boost, I haven't seen more than 1.3 bar on the Commander read out. It may go higher though.

So if i spliced into the signal wire that converts the pressure into a voltage and sends a signal to the controller, is a possible change in impedence etc going to cause any problems with either the 0-5V signal required by the AVCR, or secondly the quality of the analogue output i need.

I don't see any problems as long as the current required by whatever it is you are building stays low (milliamps).

I would use the AVCR boost sensor as long as it records vacuum OK.

Hope that helps

[Roy]

Id assume all i need is 4-20mA...i may have to wade thru the manual.

[Sydneykid]

Stick the multimeter on the AVCR MAP sensor and read of the current draw.

[Duncan]

And now can I hijack this? is it possible to run a powerfc pro directly off the factory MAP sensor on an RB26 or does it need to be changed....looking to remove AFM...

[Roy]

I think you will find that the Power Fc Pro still uses the AFMs, i think its the D-JETRO version that eliminates the use of AFMs