My niece has a '96 Civic EX with cel on. I jumpered the test connector and got a blink code 45. The manual says system too rich/ system too lean. So I checked for obvious cracked hoses, intake tube, and don't see anything. I will check for fuel pressure...what else? Looks like an original fuel filter, so we will replace that.

Thanks

 

o2 sensor.

 

while looking through the list of codes, I see a code 41 and 65 are O2 sensor fault codes...so I was thinking it wasn't the O2 sensor?

 

I am saying check the o2 sensor. It may not be failed yet, but if it has dead spots in it, it can throw the code for a rich/lean condition.