Failed California smog today. Running out of options.
May 12, 2011 11:38 PM Subscribe
Went to get my smog test done today. I almost passed it. The problem was that my engine is running a TINY bit too rich. There were more hydrocarbons and carbon monoxide coming out of my car's tailpipe than C.A.R.B. would have liked. The guy that was working at the smog test place was nice enough not to red flag my car for not having my pre-cat.
posted by RaDeuX to Travel & Transportation (16 answers total) 2 users marked this as a favorite
My car is a 2003 Nissan Sentra SE-R Spec V. Currently, it has 120k miles on it. It runs perfectly fine, minus the slightly worn syncros. The first generation of QR25DEs have had a few problems. The screws on the butterfly valves were not torqued down enough, the balance shaft had a tendency of breaking, and the pre-cat would kick up dust and damage the cylinder walls and piston rings. I put loctite on the screws and re-torqued them properly, removed the balance shaft and replaced it with a Jim Wolf Technology Balance Shaft Removal kit, and gutted the pre-cat to prevent further damage to my engine (the slight damage was confirmed by a Nissan-specialized technician, but compression test said everything is still A-OK).
I have no check engine light on, as I have an O2 sensor simulator for the O2 sensors before and after where the precat was supposed to be. As long as I have one catalytic converter, I could pass the test. Or so I thought. Apparently, the main catalytic converter is too far in the back to filter out the excess hydrocarbons and carbon monoxide.
I believe I have three options, unless I'm wrong of course.
1.) Buy the OEM headers with the pre-cat in tact. This is the most expensive route, and I doubt I have enough money for OEM headers.
2.) Weld a catalytic converter in the midpipe. I'm frowning at this option too, as it's custom work. There's also the matter of finding a catalytic converter. I'm not sure if it's still legal to buy catalytic converters separately in California.
3.) I heard that an AFC controller can allow me to change my air-fuel ratio to make my car run leaner. I have never messed around with air-fuel ratios, but I'm willing to learn more about it if it's a viable option.