Hi All and Happy New Year!

I have a 2003 Z with the ECM part number: MEC-31-522 A1. I have been dealing with my CEL... Came back as a (P0300) misfire and (P0031) Heated O2 sensor. I replaced the O2 sensor many times over. So im getting to the point where I cant think of anything the besides the ECM going bad. However, I have been looking into ECMs on ebay and whenever I look up the above part number; I always get 2005 Z ECM postings. Driven the car with the computer hooked up to see if there were any discrepancies and it seemed that my car is running fine. Even the O2 sensor is kicking back good readings.

Questions:
Can I use an ECM from another 2003 350z although the part number on the ECM maybe different [Same trim, Year, & M/T]?
Should I consider getting the ECM repaired instead?

I've been dealing with this problem for quite some time now and would really like to get my fairlady taken care of.

 

Have you verified the wiring is good with a meter

 

I have not gotten to that yet, I have an appointment scheduled with the mechanic this week to confirm the problem. Just wanted to ask some preliminary questions just in case that the ECM is the problem so I can know what to look for when replacing this part. Have you come across this kind of issue before Deadeye?

 

Not on the 350z, but you should always diagnose the issue before throwing parts at a problem.