What's the difference between P0351 and P0352?

They're the same type of ignition-coil circuit fault on different coils. P0351 is coil 'A' and P0352 is coil 'B', each mapped to a specific cylinder by the manufacturer. The diagnosis is identical — you just work on the coil, connector, and wiring for the 'B' coil.

Can I keep driving with P0352?

Brief driving is usually possible, but not recommended. A coil circuit fault typically causes that cylinder to misfire, which runs the engine rough, wastes fuel, and can push unburned fuel into the catalytic converter. If the check engine light is flashing, ease off the throttle and repair it promptly to avoid catalyst damage.

How do I know if it's the coil or the wiring?

Swap coil 'B' with a coil from a known-good cylinder. If the P0352 fault or the misfire follows the coil to the new location, the coil is bad. If it stays on the original cylinder, the problem is in the connector, wiring, or spark plug rather than the coil itself.

Will P0352 damage my engine?

The code itself won't, but a sustained misfire can. Unburned fuel entering the exhaust overheats and can ruin the catalytic converter, and a persistent misfire adds stress over time. That's why a flashing check engine light calls for prompt repair rather than continued driving.

OBD-II trouble code

P0352: Ignition Coil 'B' Primary/Secondary Circuit

The engine computer detected a fault in the primary or secondary circuit of ignition coil 'B'. It usually means a bad coil, connector, or wiring on that cylinder, and it often comes with a misfire.

Quick facts

System: Powertrain
Category: Ignition
Severity: Medium severity
Drivable: Usually safe to drive short-term
Repair cost range: $40 – $300
DIY difficulty: Intermediate DIY

What does P0352 mean?

In a coil-on-plug or coil-pack ignition system, each ignition coil boosts battery voltage to the tens of thousands of volts needed to fire its spark plug. The primary circuit is the low-voltage side switched by the engine control module (ECM); the secondary circuit is the high-voltage side that delivers spark to the plug. The ECM watches the primary circuit and can detect problems on the secondary side as well. P0352 sets when it finds an electrical fault — an open, a short, or an out-of-range condition — in the primary or secondary circuit of ignition coil 'B'.

The 'B' designation refers to a specific coil defined by the manufacturer. On many engines coil 'B' corresponds to cylinder 2, but the cylinder mapping differs between makes, so confirm it against the vehicle's service data instead of assuming. P0352 is the direct sibling of P0351 (coil 'A'); together with P0353 through P0358 they cover the full set of coils on multi-cylinder engines.

A coil circuit fault usually means the affected cylinder isn't sparking correctly, so P0352 commonly appears with a misfire code such as P0300 (random misfire) or a cylinder-specific one like P0302. The engine may idle rough, lose power, or trigger a flashing check engine light during an active misfire — a warning that unburned fuel is reaching the catalytic converter, where it can cause damage. Because the fault can lie in the coil, connector, wiring, or occasionally the ECM driver, the circuit and connector should be verified before replacing the coil outright.

Common causes

Failed ignition coil 'B' (most common)
Corroded, loose, or damaged coil connector
Open, shorted, or chafed primary or secondary circuit wiring
Worn or fouled spark plug increasing load on the coil
Poor ground or a supply-voltage problem to the coil
Failed coil driver inside the ECM (less common)

Symptoms

Check engine light on, sometimes flashing under load
Engine misfire, rough idle, or shaking
Loss of power and hesitation on acceleration
Hard starting in some cases
Reduced fuel economy
Companion misfire codes such as P0300 or P0302

Diagnostic steps

1.Scan for all stored codes and note any accompanying misfire codes to help confirm the affected cylinder.
2.Confirm from service information which cylinder coil 'B' corresponds to on this specific engine.
3.Inspect the coil connector and wiring for corrosion, looseness, melted insulation, or chafing.
4.Swap coil 'B' with a coil from another cylinder. If the fault or misfire follows the coil, the coil is bad; if it stays, suspect wiring or the spark plug.
5.Inspect the spark plug on that cylinder for wear, fouling, or an incorrect gap.
6.Check the coil's power feed and ground, and verify the primary control signal from the ECM before replacing the coil.

Repair cost

$40 – $300

A single ignition coil is commonly $40 to $200 in parts with 0.5 to 1.5 hours of labor, putting a coil replacement around $100 to $300. Replacing the spark plug on that cylinder at the same time is a common recommendation. Wiring or connector repairs run $50 to $200. Replacing all coils as a set costs more but is a frequent preventive choice on high-mileage engines.

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Open the Repair Cost Estimator with ignition coil replacement preselected. Adjust labor rate and vehicle category to fit your situation.

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DIY vs shop

This is an intermediate DIY job. It usually involves diagnostic steps, specialty parts, and some careful work in tight spaces. If you have the tools and a service manual or trustworthy video for your specific vehicle, it is achievable in a weekend. Otherwise, a competent independent shop will be faster.

Related codes

P0300 P0302 P0303 P0351