Powertrain, generic (extended)

P2323 Ignition Coil H Secondary Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P2323 concerns the spark side of coil H, the coil on cylinder 8. It is the last code of FCA's ion-sensing series: STAR case S2118000002 (2021) for the 2020–2021 Ram 1500 reads it as coil 8 secondary circuit with insufficient ionization, and an older FCA parts review lists it together with the cylinder misfire codes P0301–P0308. On such systems the coil boot doubles as a measuring path, so a loose connector, a cracked boot or a worn plug can weaken the ion signal just as a failing coil can. FCA asks technicians to reseat and lock the connector first and only then to work through the regular test plan. GM and Ford, which use coil H codes on their V8s, document only the primary side (P2321/P2322); misfire on cylinder 8 is P0308.

Likely causes

Coil 8 connector loose or not latched (FCA)
Worn or fouled spark plug on cylinder 8
Coil H boot cracked or tracking to the head
PCM ion-sense circuit faulty

Symptoms

  • Check engine light on
  • Cylinder 8 misfire, frequently stored with P0308
  • Rough running when accelerating

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–450
Time0.2–2 h

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

Parts involved

ignition coilspark plug

Related codes

P2321P2322P2320P0358P0308

References: static.nhtsa.gov, en.wikipedia.org, law.cornell.edu.