Could worn spark plugs or ignition coils cause P0300?

Yes — Worn spark plugs or ignition coils is one of the common causes of P0300 (Random/Multiple Cylinder Misfire Detected). A scan-tool freeze-frame and circuit check will confirm whether this is the root cause for your vehicle.

Could vacuum or intake manifold leak (lean condition) cause P0300?

Yes — Vacuum or intake manifold leak (lean condition) is one of the common causes of P0300 (Random/Multiple Cylinder Misfire Detected). A scan-tool freeze-frame and circuit check will confirm whether this is the root cause for your vehicle.

Could failing fuel pump or clogged fuel injectors cause P0300?

Yes — Failing fuel pump or clogged fuel injectors is one of the common causes of P0300 (Random/Multiple Cylinder Misfire Detected). A scan-tool freeze-frame and circuit check will confirm whether this is the root cause for your vehicle.

Could low fuel pressure or contaminated fuel cause P0300?

Yes — Low fuel pressure or contaminated fuel is one of the common causes of P0300 (Random/Multiple Cylinder Misfire Detected). A scan-tool freeze-frame and circuit check will confirm whether this is the root cause for your vehicle.

Could incorrect ignition timing or sensor faults (ckp/cmp) cause P0300?

Yes — Incorrect ignition timing or sensor faults (CKP/CMP) is one of the common causes of P0300 (Random/Multiple Cylinder Misfire Detected). A scan-tool freeze-frame and circuit check will confirm whether this is the root cause for your vehicle.

PowertrainWarning

P0300: Random/Multiple Cylinder Misfire Detected

The engine is misfiring on more than one cylinder, or on cylinders the computer can't isolate. A misfire means the cylinder isn't burning fuel properly — you may feel a rough idle, hesitation, or shaking, especially under load.

Can I keep driving?

Drive home / drive to a shop, but don't ignore it.

DIY difficulty

moderate

DIY possible with a scan tool and intermediate skills.

Typical cost (Canada)

$250 – $1,200 CAD

Parts + labor; varies by shop & vehicle.

Common causes

What usually triggers P0300?

1Worn spark plugs or ignition coils
2Vacuum or intake manifold leak (lean condition)
3Failing fuel pump or clogged fuel injectors
4Low fuel pressure or contaminated fuel
5Incorrect ignition timing or sensor faults (CKP/CMP)

Causes are listed roughly in order of how often they're seen on Canadian independent-shop tickets. Always confirm with a scan-tool freeze-frame and a circuit/sensor check before replacing parts.

Related codes

Other P03xx codes

P0301

Cylinder 1 Misfire Detected

P0302

Cylinder 2 Misfire Detected

P0303

Cylinder 3 Misfire Detected

P0304

Cylinder 4 Misfire Detected

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