Code p0303, misfire issues?

2002 NISSAN FRONTIER
197,000 MILES • 3.5L • V6 • 2WD • AUTOMATIC
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FLOP1134
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  • 1 POST
I have code p0303 which is misfire. I changed cylinder 3 spark plug. The wires and distributor cap are new. No catalytic converters. Still has 02 sensors. No other codes.
Apr 9, 2023 at 11:11 AM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
I would check to make sure you are getting park at #3 and if so, let's check the compression and if that is good the injector needs to be changed out.

Here are three guides to help us fix the problem:

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

and

https://www.2carpros.com/articles/how-to-check-for-ignition-spark

This guide can help as well:

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

Here is how to change out the fuel injector in case you need it. Check out the images (below). Let us know what happens and please upload pictures or videos of the problem so we can see what's going on.
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Apr 10, 2023 at 10:57 AM
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