Powertrain, generic (extended)

P230C Cylinder 3 Air-Fuel Ratio Imbalance - Adjustment At Limit During Balance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P230C is the balance-limit code for cylinder 3. On three-cylinder engines this is the last cylinder of the row; on fours and larger engines it sits further inside. The engine control trims the fuel of each cylinder separately to even out mixture differences, and P230C means the trim for cylinder 3 is used up. No manufacturer documents this exact code publicly and the NHTSA index lists no bulletin for it. Comparable data come from VW, whose 2014 Beetle table derives the plain imbalance codes from a per-cylinder fuel correction found by deliberate leaning, and from Mercedes, whose M260/M264 bulletins blame a leaking valve seat when cylinder 3 shows irregular mixture formation. A compression and leak-down test on cylinder 3 is worth doing before injectors are swapped.

Likely causes

Injector of cylinder 3 delivering too much or too little (deposits, wear)
Air leak at the intake port or injector seal of cylinder 3
Valve of cylinder 3 not sealing (worn seat or guide), low compression
Poor contact at the connector of injector 3

Symptoms

  • Check engine light on
  • Rough idle, possibly misfire on cylinder 3
  • Higher fuel consumption or exhaust smell

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–1,500
Time0.5–6 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

fuel injector cyl 3intake manifoldcylinder compression

Related codes

P219EP230BP230DP0303P0203P219A

References: law.cornell.edu, static.nhtsa.gov, static.nhtsa.gov.