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Spark Plugs and Wires
Fuel Filters
Geo Metro
Air Filters and Intake Manifolds

What do you do next if your 1995 Metro 1.0 liter still fails the emissions test on HC on Idle by 141 ppm even after you've replaced the plugs wires cap rotor O2 sensor and air filter?


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September 13, 2011 10:26AM

I had the same problem with my 92. Both the mechanic I took it to and the muffler said it needs a new catalitic converter. It is not getting warm enough in the idle mode and that is why is failing.

You should also take the car to a qualified emmissions specialist and have him pull trouble codes. There may be other reasons for your problem.


Your engine needs to be up to operating temperature. My 99 Metro had the same problem and was due to stuck open thermostat. If your water temperature gage does not read in the middle and stays near or at the bottom, then your thermostat is stuck open and you need to replace it. The needle should almost always be at the middle of the water gage and you should pass emissions.