Flex plate done, noise is gone. Now getting p0420 and occasional p0430 codes. Seems coincidental to get these codes immediately following this flex plate replacement.
Throttle body is new.
I also was getting this p0420 code about 5 years ago and it was associated with TSB 10-008-13, I had the dealership do this recall/TSB work and this code stopped.
The purpose of TSB SB-10058834-5427 was to address instances where certain Chrysler/Dodge/Jeep vehicles with the 3.6L Pentastar were incorrectly setting Diagnostic Trouble Code (DTC) P0420 - Catalyst System Efficiency Below Threshold Bank 1.
The goal of the TSB was to fix a problem where the vehicle's computer (PCM) was mistakenly thinking the Bank 1 catalytic converter was not working efficiently, even when it might have been.
Here's a breakdown of the key purposes:
Prevent False P0420 Codes: The primary aim was to reduce the occurrence of unnecessary Check Engine Lights and P0420 DTCs, which could lead to unwarranted repairs and customer dissatisfaction.
Improve Catalyst Monitoring Accuracy: The updated PCM software calibration aimed to provide a more accurate assessment of the catalytic converter's performance under various driving conditions, reducing the likelihood of false positives.
Provide a Standardized Repair Procedure: The TSB offered dealerships a specific and approved method (PCM reprogramming) to address this known issue. It ensured consistent repairs across different service centers.
Address Potential Customer Concerns: By resolving the false P0420 codes, the TSB aimed to alleviate customer concerns about potential emissions system malfunctions and the need for catalytic converter replacements.
Guide Dealers on When to Replace the Catalyst: The TSB also clarified that if the PCM reprogramming didn't resolve the P0420 code, then a genuine catalytic converter issue might be present, and replacement would be the necessary next step.
In essence, the TSB was a service action to refine the software logic that monitors the catalytic converter to avoid misdiagnosing its efficiency. It was about improving the accuracy of the onboard diagnostics related to the P0420 code.
My question- is it possible that disconnecting the battery for a long period to do the flex plate replacement reverted the ecm back to factory settings and began triggering the code again?
