Fuel and air

P2193 — System Too Rich at Idle (Bank 2)

Severity: medium Drive with care, to a shop

What P2193 means

The engine control unit uses the bank 2 oxygen sensor and fuel trim data to judge the mixture. At idle it found too much fuel in that bank, and its trim corrections ran out of range to fix it. Bank 2 is the side of the engine that does not contain cylinder 1.

Symptoms

  • Rough idle
  • Check Engine light on
  • Possible misfire or hesitation
  • Higher fuel consumption
  • Fuel smell or black smoke from the exhaust
  • Often set together with P0175 (system too rich, bank 2)

Possible causes

  1. Leaking or dripping injector on bank 2
  2. Faulty or slow bank 2 oxygen sensor
  3. Fuel pressure too high (regulator or return line problem)
  4. Faulty MAF sensor or intake pressure sensor readings
  5. Clogged air filter or restricted intake
  6. Exhaust leak or fault on bank 2 skewing sensor readings
  7. Fuel in the oil or a stuck purge valve letting in extra fuel vapor

How to diagnose

  1. Read all codes and freeze frame data, and note whether P0175 or misfire codes are present
  2. Compare short and long term fuel trims on bank 2 with bank 1 at idle and at about 2,500 rpm
  3. Check bank 2 oxygen sensor readings and response on a scan tool
  4. Measure fuel pressure and check that it holds after shutoff
  5. Test bank 2 injectors: resistance, power, control signal, cylinder balance, and leak-down if needed
  6. Inspect the air filter, intake ducting and MAF sensor for dirt or leaks
  7. Check the purge valve and smell the oil for gasoline
  8. Inspect the exhaust and sensor wiring for damage

Common fixes

  • Replace or clean leaking injectors
  • Replace the faulty bank 2 oxygen sensor
  • Replace the fuel pressure regulator or fix the cause of high pressure
  • Clean or replace the MAF sensor and air filter, and fix any intake leaks
  • Change the oil if it is diluted with fuel
  • Repair damaged wiring or connectors

Questions and answers

What does P2193 mean?

It means the engine computer found the mixture too rich on bank 2 at idle and could not correct it with fuel trim. The usual suspects are a leaking injector, a bad oxygen sensor or high fuel pressure.

Can I drive with P2193?

For a short time, such as getting to a shop, usually yes. Extended driving can harm the catalytic converter and thin out the oil, so do not put off diagnosis.

How is P2193 different from P0175?

P0175 flags a rich condition on bank 2 across normal driving, while P2193 is specific to idle. That points toward things like a dripping injector or small airflow measurement errors at low load.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.