Tuesday, October 25, 2011

93 Nissan 240SX smog check help?

I have a 1993 S13 Hatchback with 24K miles.



The previous owner failed the smog check yesterday.



The result:



M1. 15MPH

HC: MAX 88 AVE 21 MEAS 28

CO(%): MAX 0.52 AVE 0.06 MEAS 0.08

NO(PPM): MAX 704 AVE 150 MEAS 775



M1. 25MPH

HC: MAX 53 AVE 13 MEAS 24

CO(%): MAX 0.50 AVE 0.05 MEAS 0.13

NO(PPM): MAX 738 AVE 136 MEAS 507



My friend help me to do the regular maintenance services after I brought the car.



We did:



Change engine oil and oil filter

Flush coolant and fill in 50/50 coolant

Clean fuel and change fuel filter

Replace air filter

fill up 91 Octane



I just smogged the car today and it failed.



M1. 15MPH

HC: MAX 88 AVE 21 MEAS 41

CO(%): MAX 0.52 AVE 0.06 MEAS 0.12

NO(PPM): MAX 704 AVE 150 MEAS 784



M1. 25MPH

HC: MAX 53 AVE 13 MEAS 31

CO(%): MAX 0.50 AVE 0.05 MEAS 0.10

NO(PPM): MAX 738 AVE 136 MEAS 432



How do I pass the NO(PPM) with 15mph? Any suggestion? Replace O2 sensor, catalytic converter?



Thanks!93 Nissan 240SX smog check help?You changed the oil and oil filter, air filter, but you may try replacing the spark plugs with NGK Iridium or Platinum Plugs, replace the distributor, and ignition rotor, and replace the ignition wires with 8mm NGK plug wires.



Sometimes it is the simplest things that may help...if you fail again, then you can try replacing the O2 sensor. If the cataytic converter does not rattle when knocked, then it is still working.



You exhaust system does not matter for pollution, since the pollution is handled at the point of the cat. converter. The muffler does not remove pollutants, all it does is muffle the raw sound of exhaust gases and inhibit flow.