What does code P0300 mean on a Mitsubishi and is it safe to drive?
P0300: Random/Multiple Cylinder Misfire Detected. Here's what it means on your Mitsubishi, 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 Mitsubishi
- 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 Mitsubishi, 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 Mitsubishi
Mitsubishi P0300 on 2.4L 4B12 MIVEC (Outlander, ASX)—inspect coil-on-plug boots for cracking first; the boots degrade from under-hood heat at 80k–100k miles. On Galant 3.8L 6G75 V6, the coil pack assembly (single unit for three cylinders per bank) fails at 90k+ miles; replace both banks simultaneously. On Lancer Evo IX 4G63T turbocharged, P0300 during full-throttle pulls is a critical warning—check for boost leaks, fuel injector capacity, and spark plug gap (should be 0.028 inches, not stock 0.032).
Most commonly affected models