I got this cel at first start up in the morning my engine shaking at idle or even at driving.

Please help.

 

Hit an Auto Zone or depending on your demographic, Advance Auto Parts.

They have the scanner needed to diagnose and reset the CEL for free.

 

I did went to autozone but they said is P0300 n they don't know what is.

Nissan service guy tld me do not clear cel code if I do it'll never come back n Ill never know what happen to my engine after that.

 

Multiple cylinder misfiring. More info here:

http://www.obd-codes.com/p0300

 

Don't our car call have head gasket or value cover gasket?

 

Update:: we changed the 02 sensor A/F sensor 1 bank 2. They was 2 different color shown on 02 sensor n is was white n dark brown. After that engine stop shaking n it run better.

We clean MAF sensor. We also look at coil wire n spark plug none of them shown bad sysmbol. We check fuel pressure is was at 50 psi n fuel injector is in good condition.

Why did that happen n what make 02 sensor go bad?