Misfire, codes P0300 and P0181

LEO03

MEMBER
2003 MITSUBISHI ECLIPSE
3.0L
6 CYL
2WD
MANUAL
159,000 MILES

I've been having issues for a while now. Spark plugs, cables, distributor, fuel pump have been change, no leaks, O2 sensors looking good, all cables have been strapped and move out of hot surfaces areas. Have a P0181 as a possible problem, but fuel temperature sensor was replaced along with the new fuel pump. The car misfires a little bit on startup but it gets worse when it reaches is normal engine operating temperature. It feels like is adding more fuel than needed when it gets to the normal operating temperature. Downpipe was crack so I changed, thought it was the problem but is not. Also has new catalytic converter. Haven't touch fuel injectors yet. Any other suggestions please let me know. Thanks.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,747 POSTS

Hi,

I suspect the issue is related to the fuel temperature sensor. Keep in mind, the sensor doesn't have to be bad for this code to exist. There could be an issue in the wiring.

If you look at the attachments, I included the directions and pics for diagnosing the related problems for this code. Take a look through them and let me know if it is something you are comfortable doing.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-wiring

Let me know what you find or if you have other questions.

Take care,

Joe

See pics below.

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