Smog help...

[xka24detx]

Okay for who remember, my 240 was failing smog because of NOX readings of 5000ppm... and i dont really have time to find the problem, so i brough it to a old family friend who has a shop. He isnt charging me labor... just the cost of the parts or if i bring him parts. So far the EGR and vacum lines are all working and good. He changed the o2 sensor and it dropped to about 2000ppm, but i still need to get to below 900ppm. He also said my fuel pump had a small electrical problem, but he fixed it, so monday he said he is going to check the MAF, is there anything else that could be causing the problem? Thx..

[chineseb0i]

make sure there are no leaks in the exhaust..this would mess with the readings. my friend works at a shop, he was telling me bout lots of things that effect emissions..but have a tune up done if it hasn't been done recently (oil, plugs, cap, rotor, wires) also make sure ur injectors are good and no leaks. as far as anything else goes..bad nox readings can also mean you might possibly need a new catylytic converter. Since you changed the O2 sensor, then from what i can see the cat may be clogged and u might need a new one. hopefully this helps u with trouble shooting.

Solomon