why does the check engine light stay on in my 2007 Infiniti M35?
Could be any number of things....http://www.edmunds.com/car-care/what-your-check-engine-light-is-telling-you.html
get diagnostic code and we take it from there
The codes for the Infinity are not the standard codes from an ODB-II reader! I called the dealer and gave them the code and he said they didn't have such a code and wanted me to bring the car him to the shop for them to test (not for free). The code I was getting said I had a bad thermostat. The dash gauge showed normal but I changed it anyway and there is no difference in the motor temp.
Codes usually will get you close to the area you need to look, not the actual part in most instances. Sounds like the dealer wanted some diagnostic money. FInd a local independent garage to help you, might be much cheaper.
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