imported_winner007

If someone can help me out that would be great. It is a 92 civic hatch auto. My car failed on nox and it was so high. I changed mnew NGK plugs.I changed the catalytic converter and it made no diff, change the temp sensor made no diff, changed the Oxygen sensor and the nox went down. The problem is that the HC and the CO are high up a little now and not passing. What could be the problem? Any honda mechanic or someone that knows a lot about honda can help me out. I try to adjust the timing on the distributor but it didnt help at all. I've tried everything i can and replaced almost everything that needs for emissions.

My mechanic is saying it might be the computer. I have a d16z6 engine and a P28 ECU. Those 2 should be compatible.

Anyone knows why the HC and Co would fail? If so what are the common problems for the honda. Everyone say Oxygen sensor but replaced today and NOX went down a lot. Before i didn't replace the oxygen sensor my HC and CO were passing like flying colours. Now i can't even make my NOX fail since i replace my Oxygen sensor.

Reply asap for any opinions. I need this done asap because my drive clean is going to expire soon.

dingus88

she was runnign lean causing the NOX now she is runnign abit rich causeing CO and HC to be high...If you replaced the cat o2 and plugs I don't know what it woudl be...reset your ecu set your timing and run it real hard with fresh gas before etest

imported_winner007

How do u reset the ECU? Do u just unplug it and plug it back in or is there a button for reset.

dingus88

ghetto style = pull the negative ground on your battery for a few hours, then when you do start it up let it idle for a few minutes.

imported_winner007

Thanx. Anymore suggestions? No one ever had their emissions test done on their civic and failed on HC and CO? If it did what was the problem?

dingus88

o2 for the HC adn co woudl be cat and you replaced those so...??

TopDeadCenter

Cap, rotor and wires? Did you look at/replace any of these. It's the cheaper of the parts you have replaced so far. I would have started there.

imported_Dawson

when it failed nox did they use the cooling fan infront of the car its not a huge deal but it does make a difference?

imported_winner007

it's not the cap and the rotors.

Yes i did use the cooling fan all the time when i do e-test.

dingus88

well maybe your motor is done...and it's burnign oil to cause the HC and Co....maybe running lean for so long causing (NOX) helped yoru motor on it's way to the grave...if you replaced the cat o2 and did a tune up then your car should pass no problem.