Hello, so I've been dealing with the P1273 code on my G35 (05 coupe, previous owner shoved an 04 engine with an 04 ECU into it). I was wondering if a tune could maybe help with the air/fuel ratio causing a check engine light. Does this make sense?

VIN on ECU is for an 04 and the chassis is an 05.

Haven't been able to find leaks anywhere, valve covers are good, headers aren't leaking from what I can tell, and I've changed out the O2 sensors multiple times (with Hitachi ones).

I'm thinking that maybe the previous owner didn't tune it correctly, but I could be wrong. Any advice?

 

Lots going on here. Do you have to pass emissions testing? Any other modifications? Email me... seymore4 at gmail

 

Managed to pass emissions (cleared codes, drove about 30 miles, got smogged, passed, check engine light came up at around 40 miles). No mods, mainly replacing things that broke with OEM-ish parts. I'll send you an email.

 

Reflashing the ECU for a specific vehicle configuration makes sense, but first, you can precisely check the compatibility with the control unit by ordering a vin decoder at https://carfast.express/en/vin_decoder. Even with working sensors and no leaks, the Check Engine light may still come on, for example, due to an incorrect air-fuel mixture setting.

 

turns out my cats have holes in them from getting scraped somehow lmao