Hello everyone! (sorry for the long post, just wanted to cover everything)

First off, I'm going to reference this thread that I found:

https://my350z.com/forum/engine-and-...a-04-350z.html

Similar situation, only I'm going the other way. My car is a 2004.5, my engine went out at 84k, found a great deal on a local motor from a 2004 with only 32k on it.

Did the swap myself last week, everything went ok for the most part, noticed the O2 sensor plugs were different, but i was using my original harness from my 04.5, so I just used my old O2 sensors instead of the ones from the new engine.

Car started right up on the first try and seems to be running ok, haven't driven it much though. After about 10 miles, it threw a service engine soon light. Had it checked at Autozone and it was P0057 and P0420. I've looked them up and both seem like they could have something to do with the O2 sensor system. Now im reading on here that the 04.5 changed to wideband.

So now I'm wondering if there is something i need to swap out from my original 04.5 motor to deal with these error codes? Or am I going to have to get the 04 ECU and harness to fix it? My car does have resonated test pipes, and originally shot out a SES light when I installed them, but I did the non-fouler trick and it ran with no SES codes for months, until the engine went out.

Cliffs:

swapping from 04.5 to 04 motor

keeping:
04.5 harness and ECU
04.5 O2 sensors
04.5 tranny

swapping:
04 engine, everything from the throttle body to the headers

I'm kinda clueless to the O2 sensor system and wideband, and just looking for some insight. Would love to get the car running without a service engine soon light.

Thanks for any help you guys can give!

Steve

 

The '04 engine is essentially the same as the '03. Starting with the 04.5 engines, they are ULEV - Ultra Low Emissions Vehicle - hence the difference in O2 sensors.

I would have thought since you kept ECU, exhaust/O2 sensors, it would still work fine. Try putting the cats back in and see if that solves the problems. Maybe the 04 engine is too dirty for the non-foulers to work.

 

good point about the engine running dirtier, thanks for the info Dave, I appreciate it!

 

well i went home and added another non-fouler, was only using 1 before the engine swap and it was working ok, also added a small amount of steel wool, just enough that i could hold it up to the light and still see light coming through the small hole in the non-fouler. so now have 2 + steel wool for both of the o2 sensors! driven 100 miles and no SES light!

i guess it is dirtier than the 04.5