What does code P0300 mean on a Toyota and is it safe to drive?
P0300: Random/Multiple Cylinder Misfire Detected. Here's what it means on your Toyota, what usually causes it, what repairs typically cost, and how safe it is to keep driving.
What this code means
The PCM has detected misfires across multiple cylinders. This can cause damage to the catalytic converter if driven for long.
Common causes for your Toyota
- Worn spark plugs or ignition coils
- Clogged or bad fuel injectors
- Low compression
- Vacuum leak, bad MAF, or fuel delivery issue
Symptoms
- Check Engine Light (often flashing under load)
- Rough idle, shaking, loss of power
- Possible smell of unburned fuel
Typical fixes
- Replace spark plugs and coils as needed
- Clean or replace fuel injectors
- Fix vacuum/fuel issues
- Compression test if no obvious cause
Repair cost range
For a Toyota, repairs for P0300 often fall between $150 and $1200, depending on the cause and whether you use OEM or aftermarket parts. Labor rates vary by location.
Known issues on Toyota
Toyota P0300 random misfire is most often caused by aging coil-on-plug boots on the 2.5L 2AR-FE and 3.5L 2GR-FE—the rubber boot cracks at the spark plug well, allowing moisture to short the ignition. Replace all boots (and ideally all plugs and coils) as a set. On Tacoma 4.0L 1GR-FE V6, individual coil failures are common; Toyota sells coils individually. On Prius 1.8L 2ZR-FXE, P0300 combined with excessive oil consumption may indicate low compression in cylinder 1—a known issue on 2010–2015 models.
Most commonly affected models