Hey guys I just recently put a new engine in my 2006 rx8 its a manual tranny it runs perfectly fine but I have the check engine light on and its giving me the same exact codes I was getting in my old engine how can I do a real ECU reset that really works?

 

You can reset the codes using the same device you used to read the codes.
Can you tell us which codes you are getting?

 

I got the P2070 ,P0300 and something with the intake temp sensor , these were the exact same code before engine swap and I have erased them with my OBD scanner and I also did the reset removing the positive from the battery and turning key to on position for 30 seconds, and it did reset but comes right back up! My OBD scanner said something about relearning the timming position sensor! Not sure how that works!

 

Yah, if you clear them and they come back, the codes are real.

P0300
Any time you mess with the eccentric shaft sensor (such as when you remove it when replacing the engine), you need to force the ECU to re-learn the profile of the tone wheel.
Follow these directions: https://www.rx8club.com/series-i-tro...3/#post2923345

P2070
If you had this before and after the engine replacement, you have a problem with your secondary shutter valve (SSV).
Type "site:rx8club.com p2070" into google (without quotes) to get info on troubleshooting this problem.

The intake temperature sensor is inside the mass air sensor (MAF). Make sure you reconnected the MAF correctly. If it's connected, check the connector and wiring for damage. If they both look good, buy some MAF cleaner at an auto parts store and clean it thoroughly. If you're still getting this code, replace the MAF.

 

Ok , copy that , thanks will try it and get back to you!

 

Yup that worked , all codes erased with the break reset ! This time they didn't come back and check engine light is gone! Thanks for the help!

 

That shouldn't have fixed the P2070 and the IAT sensor so don't be surprised if those come back.
But at least you aren't misfiring anymore.