G'day all, I've finally got a laptop to start playing with my RB30ET, but as it has never run right since i built it i my first step is to get it run normally with basically std setup and tune.
So plug into ecu (and nistune works flawlessly) and the O2 voltage at idle is jumping from 0 vlots to 1ish rapidly. take car for spin and under load it jumps up to 1ish and is a constant smooth line on the logging. Get to a constant partial throttle position and then it starts jumping from zero to 1 again.
Now is this purely a broken wire on 02 sensor circuit (of which i cannot find) or could it be caused by something else?
Thanks in advance.
O2 Sensor Voltage Fluctuation
Moderator: Matt
Hey Brett
That is normal... its called closed loop
O2 narrow band sensor reads exhaust gas. If < 14.7:1 Air fuel ratio then reads above 0.5 volts otherwise below 0.5 volts
The ECU uses the 'read' voltage to inject mixtures to then achieve the opposite to maintain AFRs around 14.7:1 when in closed loop mode
It looks cyclic when it occurs and is normal. Do some google searching on narrow band sensors and closed loop for more information
When cold or accelerating or in a 'open loop' part of the map this will generally read really lean or really rich
When tuning, we usually disable closed loop by disabling flags in fuel map or using O2 feedback temperature / switches
That is normal... its called closed loop
O2 narrow band sensor reads exhaust gas. If < 14.7:1 Air fuel ratio then reads above 0.5 volts otherwise below 0.5 volts
The ECU uses the 'read' voltage to inject mixtures to then achieve the opposite to maintain AFRs around 14.7:1 when in closed loop mode
It looks cyclic when it occurs and is normal. Do some google searching on narrow band sensors and closed loop for more information
When cold or accelerating or in a 'open loop' part of the map this will generally read really lean or really rich
When tuning, we usually disable closed loop by disabling flags in fuel map or using O2 feedback temperature / switches
