2007 Honda Odyssey ECU relearn

What is the code you are getting? If the light keeps coming on then that tells you that you have an issue that needs to be resolved. Has nothing to with needing to relearn the computer. You erasing the code is you removing the memory from the computer. It coming back is telling you that there is an issue needing to be corrected. Do not unplug anything.

At the first time my check engine light comes on I unplugged the negative terminal of the battery , I repeated this procedure 2 times at the third I have diagnose it by the OBD2 it gives me
P0301 misfire1 cylinder1 detected the technician erased the error and then I bought NGK spark plugs and I replaced them all I see the old ones with a bad condition ( approx 86k miles ) then I have unplugged the negative battery terminal to turn off the light after that when he comes back on I get the car to another technician to diagnose the error with his OBD2 it gives
Again
Saved errors: misfire1 cylinder1 detected (new codes)
new codes: error1 2 3 4 5 6
He tells us this errors are the result of removing coils and he erased all errors
Then he tests the EGR it gives 0 and with acceleration gives (-/) (live data)
The next day the check engine light comes back on again and it stays on until know
What should I do ??? Plz help me and thank you for the first answer
Attention : the valves are always noisy should I adjust them ???

Yes, I am willing to bet you need to adjust your valves. There is a TSB on this motor for throwing random misfire codes, all cylinders misfiring..etc. The reason is because the valves are too tight and need to be adjusted. I want to say the labor rate was like 3.5 hours. Sometmes you can try to decarb the intake with seafoam and it will help.

You can try removing the EGR valve and cleaning it and the EGR ports of you can with some throttle body cleaner.

plz refer to which. TSB reference number??
Thank you for your help

I cant find the TSB number, but you can google the issue. Its pretty common issue. These engines are supposed to get their valves adjusted every 80-100k miles. On cold start ups you may here a lot ticking that goes away and have a check engine light that states random misfires or specific misfires.

Thank you very very very much

Thanks for your help

If you want please give me your mobile number to contact you
Thanks

Were you able to get the issue resolved? Sorry, but I am not going to hand out my number. You can contact me on here if you need anything. Thank you!

Ok thank you
I'm sorry hope to work with you thank you very much
I'm waiting for the genuine parts
Thank you very much

hi my dear
i did the valve adjustment and i have cleaned the EGR port and the intake manifold as well
no more misfire and no more DTC
thank you very much for your help

Awesome! Glad to hear!

I have cleaned all the egr but I don't have cleaned the egr valve
By scanning the car on live data it gives me EGR ERR 99.2%
(EGR error 99.2%) it is the egr valve ???