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Strange trim reading on GT3


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997.1 GT3


At start-up bank 1 is at -15% and bank 2 at -25% (i assume this is open loop)

Subsequently and while driving for a while both LT and ST on bank 2 are stuck at zero;

While bank1 would be fluctuating in the -10% range for LT + ST combined.


No error code or check engine but trims are either stuck at zero or bank2 will be very negative (almost -25%)

This is my first GT3 and i have been learning the car everyday

It behaves very different from my 997 C4S but seems to be the character of these cars

I found alot of initially unnerving features from RMS leaks to daily morning rattles of death, but all has become familiar to me.


However -25% fuel trim and then stuck at zero on only one bank does seem very odd !


Would greatly appreciate any other experiences with the GT3  and most importantly what do you consider to be normal fuel trims ?


 trim reading is of a bluetooth OBDII reader connected to my phone


Thanks all! 



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