Severity: ModerateChevrolet

P0305 on Chevrolet Vehicles: Cylinder 5 Misfire Detected

Cylinder 5 is misfiring. First job: work out which bank it sits on, because that decides what to check. P0305 →

5Complaints mentioning the code

#6Rank among 12 brands

0.4%Share of Chevrolet DTC complaints

In NHTSA owner complaints we analyzed for Chevrolet, P0305 was mentioned 5 times.

Notes by brand

GM's 3.1L and 3.4L pushrod V6s are well known for lower intake manifold gaskets that leak coolant into the cylinders, and the 3.8L's plastic upper plenum can do the same. A rear-bank misfire with unexplained coolant loss on one of these engines should be treated as a gasket job, not a coil job.

Most mentioned models

Chevrolet Silverado 1500		2
Chevrolet Traverse		2
Chevrolet Silverado 1500 Hybrid		1

Model years mentioned

2009: 1 · 2010: 1 · 2011: 1 · 2019: 2

Components named in these complaints

Engine (4)
Electronic Stability Control (esc) (2)
Power Train (1)
Electrical System (1)
Vehicle Speed Control (1)

Often appears together with

P0300 Powertrain The engine computer sees misfires that jump between cylinders or hit several cylinders at once. High P0121 Powertrain The throttle position reading is electrically valid but doesn't agree with engine load, airflow… Moderate P0221 Powertrain The second throttle angle signal leaves its window or stops following the plate, so power… Moderate P0304 Powertrain Cylinder 4 is misfiring. Its end or rear position makes water, oil and intake leaks common… Moderate P0306 Powertrain Cylinder 6 is misfiring. On an inline-six it's the hot rear cylinder; on GM and Hemi V8s it can… Moderate

Possible causes

Worn, often original, spark plug on a rear bank that was skipped at the last tune-up because the plenum had to come off26%
Failing ignition coil or cracked, carbon-tracked boot on cylinder 524%
Upper plenum or lower intake gasket leaking air, or coolant, into the cylinder 5 runner16%
Clogged, dripping or electrically weak cylinder 5 fuel injector12%

P0305: Diagnosis step by step →

Source: NHTSA Complaints API (US government open data), analyzed by DTC mention.