P0307 on Cadillac
Cylinder 7 Misfire Detected
P0307 on Cadillac vehicles indicates cylinder 7 misfire detected. Au7o has documented this code across 1 Cadillac model — most commonly on Escalade. P0307 means the engine computer detected a misfire on cylinder number 7 — that cylinder isn't burning its air/fuel mixture completely or at the right moment. The PCM senses this by watching for tiny slowdowns in crankshaft speed each time cylinder 7 should fire. A misfire wastes fuel, can dump raw fuel into the exhaust, and may damage the catalytic converter over time, which is why a persistent or severe misfire often makes the check engine light flash. You may feel rough idle, shaking, hesitation, or a loss of power. Typical repair costs on Cadillac range from $3,000 to $6,000, depending on the specific model and root cause.
Common Causes of P0307
- •Worn, fouled, or incorrectly gapped spark plug on cylinder 7
- •Failed ignition coil or coil-on-plug for cylinder 7
- •Faulty, clogged, or leaking fuel injector
- •Vacuum or intake air leak affecting that cylinder
- •Low compression (worn rings, burnt/leaking valve, head gasket)
- •Damaged spark plug wire or boot (on applicable engines)
- •Carbon buildup or sticking valve
P0307 on Cadillac by Model
Cadillac Escalade(1 issue)
- AFM/DOD Lifter Failure - V8 Cylinder Deactivation System2007-2020
AFM lifter collapse can affect engine-code-specific Escalades, but the original 2007-2020/5.3L-6.2L scope was too broad. Regular Escalades use active AFM in the 2010-2014 6.2L L94 and 2015-2020 6.2L L86; regular 2007-2009 6.2L L92/L9H applications did not operate active AFM, and DFM begins with the 2021 L87 outside this issue. The 2009-2013 6.0L Hybrid is a separate AFM application. Cylinders 1, 4, 6, and 7 are the designated AFM cylinders, but a tick or misfire still requires diagnosis because cam wear, oil-control faults, wiring, ignition, fuel, compression, and non-AFM valvetrain faults can produce similar symptoms.
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What does P0307 mean on Cadillac?▼
P0307 stands for "Cylinder 7 Misfire Detected." P0307 means the engine computer detected a misfire on cylinder number 7 — that cylinder isn't burning its air/fuel mixture completely or at the right moment. The PCM senses this by watching for tiny slowdowns in crankshaft speed each time cylinder 7 should fire. A misfire wastes fuel, can dump raw fuel into the exhaust, and may damage the catalytic converter over time, which is why a persistent or severe misfire often makes the check engine light flash. You may feel rough idle, shaking, hesitation, or a loss of power. On Cadillac specifically, this code is documented across 1 model.
What causes P0307 on Cadillac vehicles?▼
Common causes on Cadillac: Worn, fouled, or incorrectly gapped spark plug on cylinder 7, Failed ignition coil or coil-on-plug for cylinder 7, Faulty, clogged, or leaking fuel injector, Vacuum or intake air leak affecting that cylinder, Low compression (worn rings, burnt/leaking valve, head gasket). Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0307 on a Cadillac?▼
Repair costs on Cadillac range from $3,000 to $6,000, depending on the specific model and root cause.
Which Cadillac models have P0307 documented?▼
Au7o has documented P0307 on 1 Cadillac model: Escalade.