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monaro308
May 25th, 2011, 12:39 AM
Hi,just a quicky question.
I haven't been logging for about a year on the munro and the last time i did,i noticed that the MAP guage on V4 pro default dashboard wasn't working.
I had another play the other day and MAP is still not working.
Been working fine for 2 years.
All other readouts are working fine.
If i use Tunerpro dash,map is working fine.
Its VR V8 xml
curious to find out why
cheers..mario

Blacky
May 26th, 2011, 11:46 AM
Can you take a short (10 second) log and send the logged data file to me at paul@efilive.com and I'll take a look.
Regards
Paul

Blacky
May 27th, 2011, 11:12 AM
Hi Mario,

The MAP sensor voltage is being sent correctly by the PCM. The sensor voltage is updating correctly as the manifold pressure changes in response to throttle inputs.
However, the MAP sensor kPa value is NOT being sent correctly by the PCM. The kPa value is fixed at 94.38kPa.
I cannot explain how that could happen, it doesn't make sense. Its almost like the PCM is using two MAP sensors, a working one for the voltage signal and a faulty (stuck) one for the kPa signal.

See attached image that shows the two values' raw hex data as sent by the PCM.
You can see the first value (the voltage) changing: 37, 37, 2C, 29, 2A ....
You can see the second value (the kPa) fixed at EE.

You could try logging a different vehicle using the same vehicle definition (i.e. VR V6/V8 or VS V8) and see if it exhibits the same problem.
If the MAP kPa logs ok on a different vehicle, try replacing the MAP sensor in the current vehicle.

Regards
Paul