G
p0300
Moderate
GMC · SUVs
Random Misfire Detected
Quick Answer
Error code P0300 on your GMC SUVs means: Random Misfire Detected. This is usually fixable — see the step-by-step guide below.
Affected Models
Applies to all models
35003501400030003001150015012500
Likely Causes
  1. Faulty spark plugs
  2. Ignition coil failure
  3. Fuel injector malfunction
  4. Engine compression issue
  5. Vacuum leak
How to Fix It
1
Perform engine compression test
2
Inspect and replace spark plugs
3
Test ignition coils with multimeter
4
Check fuel injector operation
5
Scan for additional fault codes
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Spark plugs
Ignition coil
Fuel injector
Related Error Codes
Video Guides
Loading video guides…
Search more on YouTube →