Input needed, 02 sensor issues
01-25-2009, 11:06 PM
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Staging Lane
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Input needed, 02 sensor issues I have an 03 z06 and have a few questions....
I have a wideband in the car, at idle its been reading around 15.3-15.5, my long term fuel trims are maxed out +20-25%. This is with stock injectors.
Well im in the process of doing my nitrous install and obviously I want to see whats up. I figure I might have an exhaust leak causing the lean readins but im not sure. I put in the new injectors (42lb greentops), new plugs (old ones looked good by the way) and we tightened up my exhaust clamps. I rescaled the flow rate vs KPA table to match my new 42 lb injectors. Car starts up fine but goes into the same state, 15' afr idle, and long terms get into the +20-25% area on both banks.
Just as an experiment I rescale the flow rate vs KPA table to say i have about 20% smaller injectors. With these settings the trims are near perfect. but the wideband still reads lean 15's at idle.
Im guessing either my narrow band sensors or my wideband sensors or both are giving false readings and heres why:
With the near perfect trims, that means the comp thinks we are at 14.7, so either the car is really at 14.7 and my 2 year old wideband sensor is reading lean, OR the car THINKS its at 14.7 but really is not and is actually at 15.5
Is it safe to assume either the narrow band or wideband sensors are out of whack?
also my narrow band sensors were extended for the long tubes install with crimps so that could also be an issue.
I think im going to replace all 3 sensors and go from there, thoughts?
I have a wideband in the car, at idle its been reading around 15.3-15.5, my long term fuel trims are maxed out +20-25%. This is with stock injectors.
Well im in the process of doing my nitrous install and obviously I want to see whats up. I figure I might have an exhaust leak causing the lean readins but im not sure. I put in the new injectors (42lb greentops), new plugs (old ones looked good by the way) and we tightened up my exhaust clamps. I rescaled the flow rate vs KPA table to match my new 42 lb injectors. Car starts up fine but goes into the same state, 15' afr idle, and long terms get into the +20-25% area on both banks.
Just as an experiment I rescale the flow rate vs KPA table to say i have about 20% smaller injectors. With these settings the trims are near perfect. but the wideband still reads lean 15's at idle.
Im guessing either my narrow band sensors or my wideband sensors or both are giving false readings and heres why:
With the near perfect trims, that means the comp thinks we are at 14.7, so either the car is really at 14.7 and my 2 year old wideband sensor is reading lean, OR the car THINKS its at 14.7 but really is not and is actually at 15.5
Is it safe to assume either the narrow band or wideband sensors are out of whack?
also my narrow band sensors were extended for the long tubes install with crimps so that could also be an issue.
I think im going to replace all 3 sensors and go from there, thoughts?
