1992 240sx KA24DE - Won't pass emissions, spark plugs good, but smokes

[ucantstopthebick]

Hey, i tried looking up for similiar problems but didn't have any luck so if you know where i can look please just point me there.

Anyways..

My 92 240sx i took to the DEQ Center to take my emissions test for new tags. However, even after i came back and it was timed, i failed all four of my emissions, plus i failed smoke. The four that i failed are: THC: Total hydrocarbons, measured in grams/mile NOx: Nitrogen Oxides, measured in grams/mile CO: Carbon monoxide, measured in grams/mile CO2: Carbon dioxide, measured in grams/mile

the NOx is the closest to passing.. of by only 1.05the others are way off..and i am also smoking...

i timed the car also, and there is no loss of power i have it all, but somehow i failed it all and its smoking blue smoke! could it be something simple? or what should i be looking at?thanks...

[teddy]

Blue smoke means you're burning oil.

[ucantstopthebick]

yeah i know that, but then why are my spark plugs fine? they are that nice tan color, but with a strong oil odor..any suggestions why its like that?

[teddy]

Well typically when one or more of your piston rings start to go out, you'll have oil covering the spark plugs, which in this case, your rings are probably fine. Another possibility is that you've blown your headgasket. Do you have oil leaking out anywhere in the engine bay, and how fast is your oil level going down?

[rogoman]

My 92 240sx i took to the DEQ Center to take my emissions test for new tags. However, even after i came back and it was timed, i failed all four of my emissions, plus i failed smoke. The four that i failed are: THC: Total hydrocarbons, measured in grams/mile NOx: Nitrogen Oxides, measured in grams/mile CO: Carbon monoxide, measured in grams/mile CO2: Carbon dioxide, measured in grams/mile

the NOx is the closest to passing.. of by only 1.05the others are way off..and i am also smoking...

You could be smoking black smoke in combination with a little oil burning which could be misleading as just oil burning. What this would mean is that the motor may be running rich which would cause the emissions failure.

The first thing to do is an ECU fault code readout; fault codes that are posted will show which components are bad.

If the motor is running rich, the following areas need to be checked:1 - O2 sensor2 - Temperature sensor3 - Spark plugs4 - Air filter5 - Fuel pressure6 - Leaking fuel injectors

[ucantstopthebick]

my oil is fine! i haven't needed to put any in and i changed it about 2 months ago. no oil is leaking anywhere. i will try though to get some fault codes later. I was wondering htough, is there any chance that i am not passing because of my cat converter? i know that i have been scratching on bumps lately and i konw i have a hole under there somewhere..thanks for all your help guys