My 96 will not pass smog. I've had it tested for the second time yesterday after paying for it a second time, and they're saying something about trouble with the "monitors"....? Two weeks ago I changed the knock sensor and had to reset the ECU to clear the code. I was told that I'm not passing smog because the codes were manually cleared and i'd need to put miles on the car. Well, Ive driven it a little over 500mi in the last 2weeks and i'm still failing. It also has nothing to do with emissions, since I pass the emissions part. Anyone know what I can do to fix this? Any suggestions?

 

Why did you have to pay for it twice? I thought you get like a month or something to fix the problem and bring it back to them free of charge. All I can say is check the codes again just to make sure the newer ks isn't causing the problem with a ghost code.

 

Pull the codes and fix or replace whats wrong. If any codes are stored, even if the SES light is off, you'll still fail. You don't need to put xxx miles on the car after codes have been cleared, you just need to make sure that there are no reoccuring codes stored.

Make sure you get 0505 when you check the ECU.

 

thats not true. when ever you reset your ECU, like when you clear a code, your ECU needs time to check all the monitors. to fix this, you just gotta drive. you can use an ODB-II scanner to check the monitors to see if they are ready or not. if more than 2 of your monitors show up as not ready, you will fail the functional test. remember. when these monitors are not reay, it does not cause your CEL to come on so it can be a huge pain in the ***.

 

1996 Nissan All catalyst and evaporative monitors difficult to set See Nissan TSB #98-018C.

Your dealer may have to reprogram the ecu.