M6 to auto conversion

[mulot30th]

But this is not a 4l60e... this is a manual auto gear box.

I hooked the pcm line 32 and 34 to P/N switch on the transmission

Now it does show up the correct (Park / in gear (4th)) in vcm scanner.

I also set idle rpm table in Park to 975rpm and idle timing tables same in gear and park.

Problem is, when I start the engine, I need to press gaz pedal to keep it alive, as soon I let off, it just stalls.

On scanner, it shows the DESIRED RPM is 88rpm, BUT the desired airflow is correct

The result, is:

The IAC counts stays about where it belong (desired airflow)

BUT the timing drops massively (idle overspeed condition...) till the engine stalls (desired rpm is 88rpm vs current rpm around let say 750 at one moment)



What is causing this desired 88rpm DESIRED rpm?

Must be something I miss somewhere?

[mulot30th]

Did a little more investigation on what happens when


now showing 0 RPM desired in scanner when I turn key on in park, then if I shift into drive it will showup an idle rpm from the InGear idle rpm table.



PRNDL status in scanner is showing (D4 when in drive and Park when in park, so I assume wiring is correct)




Here is what I found out digging a bit more:


In park... it uses the INGEAR idle RPM table and the PARK idle airflow table

In Drive... it use the value ZERO idle RPM (coming from???) and the PARK idle airflow table


Either there is something wrong in my pcm tune? or wiring?


Right now, I am back to both pin 32 and 34 of blue connector on pcm going to GND when in P/N and that's it.


DO I need to post my current tune somewhere or is there something obvious I am missing?