The daughter just took her car for an emissions test. They just started them for the first time in the county I live in in Idaho. None the less.

88 Civic 1.6
Test Results:
READING LIMIT
HC PPM IDLE 112 220 PASS
HC PPM 2500 RPM 334 220 FAIL
CO% IDLE 0.09 1.2 PASS
CO% 2500 RPM 2.11 1.2 FAIL

Obviously it is running rich at 2500. Will a basic tune up bring this thing within the limits? Of course I could not bring it there myself and talk to the tech. The tech told her there was oil leaking into her exhaust system causing the faults???? I just re did the head about a year ago. Cleaned, lapped in the old valves and changed the seals.
Thanks
Mitch

 

I'd start by replacing the plugs, wires, cap, and rotor and by checking/adjusting the ignition timing.

Any CEL codes?

 

I think its the oxgen sensor...
Using a digital volt meter, test the connection with the vehicle running and warm. The optimum air to fuel mixture ratio is 14.7:1, and the oxygen sensor will maintain this ratio if it is operating correctly. If the engine is running lean (more air than fuel), the meter will read between 0.1 and 0.5 volts. If the engine is running rich (more fuel than air), the meter will read between 0.6 and 0.9 volts, with the ideal reading being 0.5 volts. If the reading is erratic, it could mean that the engine has a vacuum leak, or that the oxygen sensor is going bad

If you wanted to do a trick put a antifouler on both of the oxgen sensors... By doing so you are tricking the computer and making it think you replaced the sensor.. you have to drill out the anti fouler... and install it before you install the senor.. then use the volt meter and see if you see any differnt volts... Then if that fixes it.. then remove one of the foulers and test it.. so you only replace the one that is bad....

steve

 

Make sure the engine warms up to the proper temperature. If it stays cold (thermostat stuck open or wrong temperature thermostat) it will stay in "open loop" operation and run rich like it is designed to during warm-up. Check that the vacuum hose to the fuel pressure regulator is OK, having it off causes excessive fuel pressure and a rich run. Also burning a lot of oil, enough to make visible smoke, will probably cause a fail on HC and CO.

 

Sounds like I will start with the basics and go on from there. I read a little more about the law and we are only required to spend at least $200 trying to solve the problem, after that you will recieve a waiver and you are good for another 2 years

 

Idaho sounds like a nice state to live in

 

Well...had the kid take it back thru. I changed the front o2 sensor, plugs, wires,cap, and rotor.
It did much better, but still failed.
HC PPM IDLE 292(reading) 220 (limit)
HC PPM 2500 RPM 0 (reading) 220 (limit)
CO% IDLE 0.03 (reading) 1.2 (limit)
CO% 2500 RPM 0 (reading) 1.2 (limit)
The only thing I forgot to do was the timing. I will try that tomorrow and have her run it thru again. If you look at the beginning of the post originally it had passed the HC at idle with a reading of 112.
Like always thanks for your help everyone.
Mitch