Failed Emission Test

May 06, 2004 3 Replies

Hi, I have a 95 ford contour that recently failed the emission test. I can usally replace parts myself but don't really know how to diagnose problems. Can anyone tell me why the HC reading is so increadibly high? Thx.



Standard Reading Result Standard Reading Result HC (ppm): 123 865 FAIL 128 1004 FAIL CO (%): 0.69 0.72 FAIL 0.71 0.65 PASS CO2 (%): 14.9 15.0 O2 (%): 0.0 0.1 Nox (ppm): 878 53 PASS 970 47 PASS DILUTION: >6.0 15.6 PASS >6.0 15.7 PASS


Start with new plugs. I recently had this same issue with plugs that looked OK but one of them was misfiring (not enough to feel) for whatever reason. If that doesn't do it try the distributor rotor, then the cap and wires, then the coil.

Tim

I'd check your PCV valve, change your oil and change the spark plugs. How many miles are on your car and how good are you at routine maintenance? Could also be a clogged air filter.

-Bruce

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