1987 Suzuki Samurai Smog Test / Spark plug temp. range

1987 SUZUKI SAMURAI
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DIJITWRX
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Engine Performance problem
1987 Suzuki Samurai 4 cyl Four Wheel Drive Manual 135K miles

87 Suzuki Samurai failed CA smog test with a fresh head, plugs, cap, rotor and timmed to perfection. HydroCarbon count was 54 points over the allowable limit (rich mixture/un-burnt fuel) everthing else passed . . . The Hitachi Carb is preset at the factory, one must remove the carb and remove a set pin in order to make any adjustments to the mixture.

The question: If I install a "hotter" spark plug, will this aid in burning the excess fuel and reduce the HC level seen at the smog station and thus "possibly" passing?

Thanks,
- - - Dave
Jun 26, 2009 at 7:44 PM
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RASMATAZ
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Hydrocarbon failures mean unburned gasoline is passing through the engine and entering the exhaust. The three most common causes include ignition misfire, lean misfire and low compression (typically a burned exhaust valve). Ignition misfire can be caused by worn or fouled spark plugs, bad plug wires or a weak coil. Lean misfire results where there is too much air and not enough fuel, so check for vacuum leaks, dirty injectors or a fuel delivery problem. In addition to these, hydrocarbon failures can also be caused by oil burning due to worn valve guides, valve guide seals and/or rings.
Jun 27, 2009 at 2:18 AM