Code po300

2003 GMC SIERRA
119,000 MILES • 4.8L • V8 • 2WD • AUTOMATIC
Avatar
GLENN VAN SCYOC
  • MEMBER
  • 1 POST
Misfire, check engine light.
Mar 25, 2019 at 1:19 PM
Advertisement
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.
Avatar
SEVAG P
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 405 POSTS
Hello thanks for using 2CarPros.

For the fault code p0300 misfire run our guide.

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Let us know what happens.
thank you.
Mar 25, 2019 at 1:49 PM
Avatar
SEVAG P
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 405 POSTS
Misfire is a result of no proper combustion inside a cylinder that causes absence of spark, fuel or low engine compression.

Check for spark run our guide:
https://www.2carpros.com/articles/how-to-test-an-ignition-system

Check injector pulse run our guide:
https://www.2carpros.com/articles/how-to-test-a-fuel-injector

Check engine compression:
https://www.2carpros.com/articles/how-to-test-engine-compression

Feed back the result we are interested to know the problem.
Thank you

Mar 26, 2019 at 1:31 PM
Advertisement