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I barely passed CA smog after a new catalytic converter. The car runs great.

(1999 Saturn SC2)
in Victorville, CA on January 05, 2015
I don't want to lose the car. It has lower compression, 150 instead of 180, so probably head gasket leaks some, but it has fine power for me. Have new O2 sensors, had carbon buildup cleaned out, new plugs etc., but it was still close to high on carbon output. Is there a way to upgrade the catalytic converter yet still match the Aftermarket Catalytic Converter Database? I had a new cat, and the state said it was "incorrect." Bought a new one, now it's "in compliance with CA regulations, certification level TLEV." I ay in compliance, but even new, I barely passed. Is there a way to upgrade the cat rather than replace the head gasket for $1800? Thank you.
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Popular Answer
on January 06, 2015
Head gasket is most likely NOT your cause of low/even compression. Car is OBDII , so in your best interest , find a competent shop that knows how to interpret data , while it's running , start with 'fuel trim' readings.
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on January 07, 2015
Thanks. That gives me hope. I'll start doing research on fuel trim readings and how to read OBDII. After my new cat and passing smog, I accidentally let the engine idle for 3 hours, so I don't know if that created too much heat or build-up for this upcoming test. Probably the best thing is to have it pre-tested, and gradually eliminate problems, rather than worry. 205K, with a rebuilt engine, but it's so nice. I hate CA telling me I have to get rid of it. The first requirement way back in 99 was something like 0.57% for HC, and CA seems to want to keep lowering the numbers.
on January 06, 2015
Dirty engine oil contains a lot of carbon. If the carbon was cleaned from the engine and the oil was not changed. That could cause high CO2 reading.
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on January 07, 2015
Thank you. Yes, I did a two big expensive carbon flushes, and oil change, new plugs and wires, new hoses, new thermostat, new valve cover gasket,new air filter, more new 02 sensors, new ECTS, new fuel pump filter. I have probably driven 15K this year after all this.
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