P0302 on Saturn: How to Diagnose & Fix
Cylinder 2 Misfire Detected
3 Saturn models · 3 documented issues · $50-$800 repair
P0302 on Saturn by model: symptoms, diagnosis and fix
The Saturn S-Series uses a Distributorless Ignition System (DIS) with a waste-spark coil pack mounted on top of the engine. The coils and the Ignition Control Module (ICM) fail with age, throwing P0300-series misfire codes (commonly P0301 or P0302). A subtle but documented contributor is poor grounding: the ICM grounds to the transmission bellhousing via a stud, and corrosion on this ground path causes intermittent misfires that are easily misdiagnosed as coil failure. The waste-spark design uses the #4 plug firing on the compression stroke to fake a cam signal, so if the #4 coil weakens, the DIS may also lose its cam-position reference, causing cascading driveability issues.
Common Symptoms
- Misfire DTC P0301, P0302, P0303, or P0304
- Rough idle or shaking at idle
- Hesitation or stumble on acceleration
- Check Engine Light (often flashing under load)
- Reduced fuel economy
- Hard starting when warm
How to Fix
Diagnose by swapping the suspect coil with a known-good cylinder coil — if the misfire follows the coil, replace it. Before condemning the coil pack, inspect and clean the ICM-to-transmission ground stud: remove the bolt, wire-brush the contact surface on the transmission case down to bare metal, apply dielectric grease, and reinstall. Also clean and grease the ICM connectors. If grounds and coil swap don't fix it, replace the full coil pack assembly (~$80-150). Always replace the spark plugs and plug wires at the same time — the OE Champion plugs are specified for this engine; aftermarket platinum/iridium can cause its own misfires on the waste-spark system. Torque coil bolts carefully; the aluminum threads strip easily.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- AM Autoparts AM-25049835 Saturn 1.9L DIS ignition coil
Two coils are used; order only the diagnosed quantity and confirm model/year.
- Standard Motor Products LX-385 ignition control module
Confirm OE interchange and connector before purchase; not the 1996-1999 branch.
- Genuine GM 19178836 electronic ignition control module
Not for 1991-1995; confirm VIN/model and connector.
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (4)
The 3.6L V6 Auras are reported to throw misfire codes, frequently as a downstream symptom of the stretched timing chains but also from worn ignition coils/spark plugs or carbon buildup on the direct-injection intake valves. Owners experience rough idle, hesitation, and a check engine light. P0300 with cylinder-specific misfire codes is common.
Common Symptoms
- Check engine light (often flashing)
- Rough idle / shaking
- Hesitation or stumble on acceleration
- Reduced fuel economy
How to Fix
Diagnose root cause: inspect/measure timing chain deviation first (since chains are a known weak point), then replace spark plugs and any failed ignition coils. Walnut-blast carbon from intake valves if buildup is present. Address timing chains if correlation codes accompany the misfire.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine GM spark plug 19300872 (replaces 12597464)
Confirm VIN/engine and current supersession before ordering.
- Genuine GM ignition coil 12632479
Confirm VIN/connector and current supersession.
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (2)
On the 3.0L and 3.5L V6 Vue models, the valve cover gaskets become brittle and leak oil down into the spark plug tubes. The oil soaks the coil-on-plug boots, causing the rubber to swell and degrade so spark grounds out, producing misfires and rough running. Oil also drips onto the exhaust manifold, creating a burning-oil smell.
Common Symptoms
- Engine misfire
- Rough idle / poor performance
- Burning oil smell
- Oil in spark plug tubes
- Check engine light (misfire codes)
How to Fix
Replace the leaking valve cover gaskets and clean oil from the spark plug tubes, then replace the oil-soaked coil boots (and plugs if fouled). Replacing only the boots without fixing the valve cover gasket leak leads to repeat failure, so address the gasket as the root cause.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Beck/Arnley 036-1708 two-cover gasket and tube-seal set
Not the 2002-2003 3.0L, four-cylinder or 2008-2010 V6 branches; confirm engine/VIN and inspect covers for damage.
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (4)
- Saturn Vue: Bad Coil Packs → Symptoms and Diagnosis | Drivetrain Resourcearticle
- Saturn Vue Ignition System Guide: Replacing Your Coil-on-Plug Boots (2002-2010) | Go-Partsarticle
- Engine Oil Leak From Valve Cover Gaskets: Saturn Vue | RepairPalarticle
- 2005 Saturn Vue CYL 3 misfire — oil in spark plug wells, valve cover gasket fix | ScannerDanner Forumforum
P0302 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0302 mean on a Saturn?
P0302 stands for "Cylinder 2 Misfire Detected." This code means the engine computer has detected a misfire specifically in cylinder 2, meaning that cylinder isn't completing combustion properly on some firing events. The computer watches tiny variations in crankshaft speed to spot when a cylinder fails to fire, and a misfire means the air-fuel mixture isn't igniting correctly — usually from a spark, fuel, or compression problem in that cylinder. You may feel a stumble, rough idle, shaking, loss of power, or a flashing check-engine light, and persistent misfires can damage the catalytic converter. Because it names a single cylinder, the fault is often a component serving just cylinder 2, like its coil, plug, or injector. On Saturn it is documented across 3 models: S-Series, Aura, Vue.
What are the most common causes of P0302?
The most common causes of P0302 are: Worn or fouled spark plug (cylinder 2), Failed ignition coil or coil-on-plug (cylinder 2), Clogged or faulty fuel injector (cylinder 2), Vacuum or intake air leak affecting that cylinder, Low compression (worn rings, burnt/bent valve, head gasket), Damaged spark plug wire or boot (if equipped), Carbon-tracked or cracked coil/plug causing spark loss, Faulty PCM/ECM driver (rare). The specific cause varies by vehicle.
How much does it cost to fix P0302 on a Saturn?
Published repair estimates on Saturn range from $50 to $800 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0302 on a different make?
View P0302 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.