Hi,
It seems you know what to check for. Do you feel the misfire when driving? Is the engine running okay or does it seem to have a loss of power?
There are a lot of things that can cause a random misfire. A partially clogged catalytic converter, leaking fuel injector, low engine compression and so on.
Take a look through this link and let me know if anything helps:
https://www.2carpros.com/articles/engine-misfires-or-runs-rough
Take a look through this link and let me know if this is how you checked for vacuum leaks:
https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge
If you have a live data scan tool, check the short term fuel trims and let me know what you find. Also, if you have noticed a power loss, you can try removing the O2 sensor before the catalytic converter to see if it makes a difference as far as power. Here is a link that explains the symptoms of a converter issue:
https://www.2carpros.com/articles/bad-catalytic-converter-symptoms
Let me know also if you checked engine compression. Low compression can create a misfire as well.
Take care and let me know.
Joe
Oct 27, 2020 at 5:47 PM
