2005 Nissan Pathfinder
Mileage
415,481
Service Date
3/29/2024
Services Performed
- Failed for MIL on Codes: P0430
- Catalyst Efficiency Low (B2) P2138
- Wrong APP Sensor Rationality Signal Engine Faults: P0430
- Catalyst Efficiency Low (B2) P2138
- Wrong APP Sensor Rationality Signal All Monitors are complete. Mode-6 test results for cats show good passing range on bank one, and solid failure on bank two. Road test and monitor all AF/O2 sensors and fuel trims. Looks like last time it was smogged and failed in December, it failed for the P0430 code and P0455 EVAP large leak. EVAP fault not present now and monitor is complete. Right (Bank 1) bank cats and upstream A/F sensor have been replaced with legal aftermarket units. Bank 2 cats are both still original/OEM. Road test and monitor fuel trims and all four AF/O2 sensors on graphing scanner. Confirm the B2 downstream sensor shows excessive switch rate, nearly matching the front sensor's rate on cruise. All sensors range out normally under full rich and lean conditions. Needs bank 2 front catalyst replaced. Need to also replace B2 upstream A/F sensor with catalyst. Sensor appears to be original and likely will be seized or will fail upon removal and installation process. New sensor will help ensure maximum catalyst life. When coming to a stop after driving on freeway the traction control lights came on and engine started running rough and had no throttle response. P2139 reset at this time. Review scan data for both APP sensors during fault and found the APP 1 signal to be well under the minimum limit for no-pedal. Normal closed-throttle reading for APP 1 is .65-.86 volts. Actual was .48v. APP 2 was in normal range. APP 1 would respond to pedal movement but was also lower than expected at wide open position. WOT range should be 4.3v or more. Actual was 3.8v. Overall range was biased low. Voltage returned to normal after sitting still for a few minutes. APP 2 values were never outside normal. Monitored the 5v reference circuit at APP1 while road testing again. When issue occurred again the reference circuit was still normal at 5.1V. Issue cannot be signal ground as a high resistance in signal ground would cause high sensor signal range, not low. Fault is internal to APP sensor. Replaced the APP sensor only per BAR instructions, then returned to customer for drive cycle/monitors. Customer returned next day with MIL on, CAT and EVAP incomplete, and current code P1283 A/F Sensor B2S1 Circuit Fault. Found intermittent flat line of sensor signal on road test. Need to replace the B2S1 A/F now and see if cat monitor will complete.
- ACCELERATOR PEDAL POSITION SENSOR – Remove & Replace – [Includes: Perform Relearn procedure.]
- AIR/FUEL RATIO SENSOR – Remove & Replace – Upstream Oxygen Sensor,One
- CATALYTIC CONVERTER – Remove & Replace – Front,One,Left
- Smog inspection
- Certification fee
Marc M. gave our service a 5 star review on 3/29/2024
