I'm throwing a CEL of code 72, which is random misfiring of cylinder 2, and a code 74 which is random misfiring of cylinder 4. I've changed the plugs maybe like 6 months ago. My wires are factory, probably a little over a year old. The mechanic said the timing wasn't out of spec. The only thing I could think of is changing the cap and rotor, which has never been done for the life of the car. (97 LX sedan, stock motor). Any input would help, I dont want to spend money on parts that wont fix the problem. Once these CELs are cleared i can finally pass the smog check. TIA

 

bump

 

I had a code 71 about a month ago. Swapped the plugs, cap, rotor (About $30-35 dollars for all of it), and had dont my plug wires just recently before hand. Cleared the light and it hasnt come back.

Did you notice your car running rough? Did it have a hard time starting up and threw the code? Or were you just driving along one day and the CEL came on?

Start with cap/rotor/plugs/wires first and go from there.

 

Thanks man, just what i was looking for, someone who had the experience. Well I guess the car has been rough. I didnt notice until a buddy of mine commented on it. The CEL was never on till after I failed the 1st smog check. By the way, how do u clear the codes after the problem has been fixed? The smog tech told me there has to be no CELs on in order to pass. He also said once the problem is fixed i have to drive it for at least 100 miles before getting the test done again.