cant pass monitors

[loser101]

I have a 1996 se. I tried to get it smogged, its passs emissions with no problem, but didnt pass monitors. I have been driving it for a month now about 1500 miles and still cant pass. The monitors i have left is o2 and cat. The o2 senser is pretty new (less then a year old). The car doesnt throw any codes and goes into closed loop. I also tried to do the drive cycles and still nothing. If any of you had this problem please help.

Thanx,

Oleg

[motonagam]

Hmm, it should have run all the monitors by now, given that you've driven it for 1500 miles. All the monitors can run, but not necessarily pass all of them if it has a problem. Do you mean you can't get the monitors to run, or do you mean the monitors has run, but didn't pass? If the monitors hasn't run, then there's something keeping it from running. For example, the oxygen sensor monitor has to run and pass first, before it can run the catalyst monitor, because it uses the oxygen sensors to detect catalyst efficiency. If the monitors ran, but did not pass, then it should have stored a diagnostic trouble code. In order to pass the OBD2 functional test, you need to pass all the monitors except one, so if you can get one more to pass, then you are good with the smog test.

[loser101]

WHen i scan my car it says that the monitors are not ready. And i have been checking for codes, nothing comes up.

[motonagam]

Hmm, then something must be keeping from running the monitors. I don't know why it's not running, because it should have ran by now. Hmm... it could probably even be a bad ECU... I dunno. Sorry I wasn't any help.

Oh, and when I said, "In order to pass the OBD2 functional test, you need to pass all the monitors except one, so if you can get one more to pass, then you are good with the smog test," I really meant all the monitors has to run except one, but whichever monitors ran ALL has to pass. Just clearing it up so there's no confusion.

[TibDrifter]

i also i a 96 240sx as well and i had the same problem as you did, pased all the gas but the 02 and cat monitor failed, drove for days and still nothing. so i clean piped the car and swaped an sr.that didnt help did it, but i hope this helps, later on during my swap i found one of the fuse for my heated o2 was burned, so check the fuse box and if it pass let me know and but my mind at rest.haha Just kidding.there is a TSB as well on all OBDII for all nissan so check that as well. good luck

[nistech]

Hmm, then something must be keeping from running the monitors. I don't know why it's not running, because it should have ran by now. Hmm... it could probably even be a bad ECU... I dunno. Sorry I wasn't any help.

Oh, and when I said, "In order to pass the OBD2 functional test, you need to pass all the monitors except one, so if you can get one more to pass, then you are good with the smog test," I really meant all the monitors has to run except one, but whichever monitors ran ALL has to pass. Just clearing it up so there's no confusion.



wrong info.
it will pass the bar 97 smog test if only 2 moniters arent set
(it is minimum of 2 not ready)

and i dont think u need a new ecu if they arent getting set clear the codes and try again b4 u go messing around with ur ecu

[motonagam]

wrong info.
it will pass the bar 97 smog test if only 2 moniters arent set
(it is minimum of 2 not ready)


I'm not doubting you, but if it's true, I wonder why the OP didn't pass the smog inspection for the readiness monitor tests, because he did say the only thing left to run is the oxygen sensor and the catalyst monitors. He also mentioned that he has no stored DTCs, so I don't see how he could have failed. Weird.

[nistech]

maybe at the time it was 3 and now he has 2.
i ve tested a ferrari 360 modena which had 2 and it failed and i checked the moniters after words and it went up to 3 it was pretty weird
i ve always had a big problem with porsches getting them ready is a bitch. my friend has the computer that tells u what to do while driving and u go step by step and he gets them set in like 15 mins.

and today i had a guy come in he had 400 miles on it and they were still not ready only 1 monitor was ready. the car has a problem with the thermostat never gets fully hot so i think that is the reason why he had that problem.
but anyways just unplug the battery and try again.

[loser101]

That is true first time i went i had o2,egr and cat and since then egr passed. I hope it is a min of 2 because i REALLY need to get it done.

Thanks for the info guys.

[motonagam]

ok, that explains it. haha. If that's the case, bring it back to the smog station and see if it passes this time. Don't clear codes, otherwise it will reset all the monitors with it, and you'd have to start over. Good luck!