HOW TO REPAIR POST CATALYST FUEL TRIM SYSTEM HIGH LIMIT CODE P2097
My car has 83830 miles.
My car has an automatic transmission.
Hi there. For your vehicle’s P2097 (post catalyst fuel trim system too rich bank 1) code, this can be difficult to diagnose. For all intents and purposes, the vehicle’s PCM (powertrain control module) has recognized too much fuel and not enough air at the post O2. The O2 sensor(s) provides this information to the PCM. A scanner with parameter capabilities will be necessary to accurately diagnose the problem.
The long term fuel trim(s) will show whether the PCM is attempting to correct any condition in fuel delivery. Driving the system lean or rich to compensate for the information provided by the O2 sensor(s). This parameter is in percentages and mid-range is 10-12%. Above the mid-range, the PCM is driving rich. Below the mid-range, the PCM is driving lean. The O2 sensors generate their own voltage 0-1volt, based on oxygen content in the exhaust. Above .5volt indicates rich (low oxygen content). Below .5volt indicates lean (high oxygen content). The pre-catalyst O2 sensor need to be operational and accurate before condemning, the post-catalyst O2 sensor.
It could be, a faulty O2 sensor. It could be, a connection or wiring harness fault, It could be, a faulty PCM. I recommend having your vehicle’s P2097 trouble code diagnosed and repaired by a certified technician, such as one from YourMechanic.
Have a car question? Get free advice from our top-rated mechanics.
Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing