What to do about pre-cat failure In California

2002 Protege 5
I've had my P5 for two years, and I've had the precat failure this entire time. I've ignored it and just went about my merry way until now.

I need to smog it, and sell the car. It's been a fun car most of the time but I need to get this fixed or passably fixed.

I read about the non-fouler and the resistor thing (forgot what it's called).

But I'm in California, so having the spacer in there likely isn't going to fly with the visual inspection.

I thought about replacing the precat but between the cost of the part and the time to wrench on it, bust two knuckles, lose my voice from yelling at that one bolt that won't budge I'm not sure it's worth it, the car it pretty worn out and has some dents and paint issues.

What are your experiences with this? Recommendations? I'm already a month past due on the smog (smash)


1999 mazda protege
I live in ca. Did the non fouler on two different proteges for p0420 and passed smog flying colors.

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06 Mazda 3 Hatchback GT
It all depends on the shop. Some shops go over stuff with a fine tooth comb, others just smog and collect your money.
Mazda Protege5
Exactly. I also passed with the non fouler and thought someone might catch on. I just replaced both my precat and 2nd cat and it wasn't that bad. I had more trouble getting those black rubber supports off (The hold the 2nd cat suspended in the air from both sides) than any of the wrenching I did.
2002 Protege 5
Hi guys, didn't mean to abandon this thread.

I'm going to replace the precat. I have a decent knowledge and won't have trouble replacing it except the bolts and rubber stuff (Shakes fist in air).

One question, I don't hear and exhaust leak anywhere nor a ticking noise from the e. manifold. What's the chances it's the downstream sensor? I'm only getting the pre-cat code no 02 sensor codes.
2002 Protege 5
Are the 50 state CA CARB physically different than the 49 state versions?

I understand what CARB is in California. But I'm curious is they are manufactured differently? Or one just has the CARB stamp on it.