[quote name='Cheers!' date='Mar 25 2005, 04:37 PM']02 sensor should be placed as far down from the engine/turbo as possible. All wideband o2 sensors have their in built in heater control, it is better to let the digital control of the o2 sensor's control box regulate the temperature than to risk getting inaccurate readings of the o2 sensor being constatnly overheated with the control box trying to cool the sensor down by sending zero current to it.


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What he said X2



There is not much difference at all in responce time especialy when dealing with part throttle and above so the further back the sensor the better I find, this is only limited by the use of CAT's etc.... Only real thing ot look out for is a leaky exhasut system that can skew readings as well but generaly further back I find the best.