Ok well i just got a 90 civic dx like a month ago and the deal was i was going to smog it.. well i just did today i did a pretest for 20 buxs here and it falled.. one this it said is modified PCV valve... so i looked at that and i changed the tube on it because i saw it was ripped right where it conects on the valve.. i also just replaced the valve to...well it failed in the NOX area everything else is fin and it only failed in the 15MPH section well here are the numbers


NOX(PPM)
MAX AVE MEAS
835 237 894

well let me know what u think it is.. i did change the oil about 1 month ago and i did a thing called engine flush then.. so im thinking maybe do another oil change right now and then but that NO SMOKE addative in my oil and it should fix my problem>? well

 

retard your distributor timing, and get some "guaranteed to pass" or the like from NAPA.

keep the car at operating temps before you get the test done...

 

Never use any oil additives.

Except maybe for an oil flush ie Seafoam since you only run the car for a few miles and then change it out anyway.

Like he said, retard the timing and maybe use a higher octane. Your motor is running hot.

 

u need to post up ur smog test vir
4 us to help u
all 4 gases r related to each other.....

and no ur oil change with the addative didn t hurt emmission.........

 

alright in a little bit ill post all of my ratings... thanks

 

89civic racer: If you have any smog related questions, eail me.