17 LHO2S inversion error Yes
24 RHO2S inversion error Yes
Codes 15 & 17: LHO2S Inactivation and/or Inversion
Codes 23 & 24: RHO2S Inactivation and/or Inversion
Sensor Purpose:
The oxygen sensors are located in the downpipes in the exhaust manifolds. There are two sensors, one on each bank (California cars may use additional sensors). The radiator-side of the engine is known as the "left" side and codes 15 and 17 apply to it. The firewall side of the engine is known as the "right" side and codes 23 and 24 apply to it.
The sensors are used to tell the PCME what the oxygen content in the exhaust stream is with respect to the ambient. From this, the PCME makes corrections to the injector pulse widths to maintain stoichiometry (i.e. about 14.7:1 air/fuel mixture). The sensors are used only when hot (they use heater elements to speed heat-up and reduce cold-start emissions) and when in "closed loop" mode (i.e. WOT is not closed loop).
A sensor will generally produce about 500mV output at stoich. When rich, the output voltage reaches a value above 500mV and when lean, the voltage falls below 500mV. The PCME tries to maintain 500mV average O2 sensor voltage so the averaged mixture is about 14.7:1.
The O2 sensors have 4-position connectors on them:
RHO2S Wire Colour LHO2S Wire Colour Purpose
R/BK R/BK Heater element supply from main relay
BK BK Heater element return (ground)
BK/Y DB/W Sensor output
BK/DB BK/DB Sensor return
Fault Description:
Inactivation errors 15 (left) & 23 (right) indicate the sensor never "woke up" from cold. Cold sensors produce little or no output voltage. Once the engine RPM exceeds 1500RPM, the PCME expects to see the voltage on the sensor(s) go above 500mV within 100 seconds. If it does not, the inactivation code gets set.
Inversion errors 17 (left) and 24 (right) occur when the sensor stops responding to the PCMEs adjustments to the A/F ratio. Inversion refers to the sensor swinging back and forth (or inverting) across 500mV as the PCME alternately makes the A/F ratio slightly richer or slightly leaner. If the sensor does not mirror theses changes, the PCME will set the inversion code.
PCME Fault Control Moding:
When any of codes 15, 17, 23 and 24 are set, the PCME falls out of closed loop mode and instead relies on calculations rather than feedback to control the A/F mixture. The effect will be lowered gas mileage, smelly exhaust, carbon accumulation etc.
Memorization:
This code is memorized in the PCME non-volatile memory.
Things To Check When Diagnosing:
The generally accepted solution for these errors is to replace the offending sensor, assuming no connector or wiring fault exists.
For codes 15 and 17, replace the left (radiator-side) O2 sensor. For codes 23 and 24, replace the right (firewall-side) O2 sensor.
1 long could be 10 which is intake air sensor. although 7 long would be 70 and as far as i know there is no code 70...
crank sensor code is 2 so 2 quick flashes. hows your mileage? is it a constant misfire? how old are your ignition parts? could also be a bad injector. have you found out what cylinder isnt firing?
