P2190 indicates the engine control system is detecting an excessively rich air-fuel mixture at idle on Bank 2 (the engine bank not containing cylinder #1). The fuel trims have reached their maximum corrective limit attempting to compensate for excess fuel.
One or more injectors may be stuck open, leaking fuel, or have incorrect spray pattern causing excess fuel delivery to those cylinders.
The oxygen sensor may be contaminated, failing, or sending consistently false rich readings to the PCM, triggering excessive fuel enrichment.
A stuck or failed pressure regulator, or fuel pump/filter issues, can cause excessive fuel pressure leading to rich condition.
A dirty or failing Mass Air Flow sensor may report lower airflow than actual, causing the PCM to deliver more fuel than needed.
If the evaporative emission purge valve is stuck open, it can allow excessive fuel vapor into the intake, creating a rich condition.
Rarely the cause. The PCM may have a software issue or internal fault, but all other causes should be ruled out first before replacing the control module.
Short distances may be possible, but prolonged driving with a rich condition can damage the catalytic converter from excess unburned hydrocarbons, foul O2 sensors, and waste fuel. Address the issue promptly.
The PCM is almost never the cause of P2190. This code almost always points to a fuel system, sensor, or vacuum-related issue on Bank 2. Reputable technicians will diagnose and rule out all physical causes before considering the control module, which should be a last resort.
No. Bank 2 simply refers to the engine bank that does not contain cylinder #1 - this is a specific side of the engine. The causes are typically limited to components on that specific bank (injectors, O2 sensor, vacuum lines).