Cant pass CA smog!!!
- Thread starter macatoni
- Start date
Hi Macatoni-
You got some good advice. NOX is related to a number of things:
1. EGR: Its only function is to reduce NOX.
2. Over-advanced timing
3. Overheating
4. Lean A/F mixture
5. Compression over specs
6. Sometimes is high for mysterious reasons (not a frequent thing). Use cooler plugs and/or TurboTweak smog chip.
I just passed California "Test Only."
At 15 and 25 MPH my car read:
HC: 10 and 41
CO: .01 and .55
NO: 6 and 6
At idle before test:
BLM: 142 (typically warms at 128 and after, idles in 130s...just decided to act up for test)
TPS: 15 (typically runs 20 -25)
IAC: 42
TEMP: 192 (a 180 thermo)
Car had synthetic oil and is stock. For test, I used stock oil filler tube, stock, turbo to pass. valve cover elbow, stock air cleaner box.
A good foundation is required to pass smog...
New oil, new filter, clean throttle body (they can get really sooted up), clean up pipe, good plugs and wires.
Important: New vacuum lines-especially those linked to EGR system...there can be leaks in old lines that you will not see (trust me). If you suspect EGR, buy a new one...I have a strong feeling this and the related vacuum lines are involved. I would also check the filter on the EGR solenoid to make sure it is not clogged.
A fuel additive, Guaranteed To Pass, can work as extra insurance. I used it, but think the car would have passed without it anyway...I'm sick and tired of smog tests and like to be over-prepared for them.
Finally, get the car hot before the test. Then make sure the technician heats the car to "closed loop," then lets it idle at least for 5 minutes and gets it heated up so the CAT works well.
Don't be discouraged. Be methodical and thorough...you are just getting a machine to run clean. Remember, it has had some time to get dirty.
You will eventually pass. Sure it's frustrating sometimes, and you may have to throw some money at it, but we all go through this and learn what works for our own cars.
Steve
PS Went to school in Berkeley...please give my regards to the beauteous bay! And, toss down an Irish coffee or two at the Buena Vista for me.
You got some good advice. NOX is related to a number of things:
1. EGR: Its only function is to reduce NOX.
2. Over-advanced timing
3. Overheating
4. Lean A/F mixture
5. Compression over specs
6. Sometimes is high for mysterious reasons (not a frequent thing). Use cooler plugs and/or TurboTweak smog chip.
I just passed California "Test Only."
At 15 and 25 MPH my car read:
HC: 10 and 41
CO: .01 and .55
NO: 6 and 6
At idle before test:
BLM: 142 (typically warms at 128 and after, idles in 130s...just decided to act up for test)
TPS: 15 (typically runs 20 -25)
IAC: 42
TEMP: 192 (a 180 thermo)
Car had synthetic oil and is stock. For test, I used stock oil filler tube, stock, turbo to pass. valve cover elbow, stock air cleaner box.
A good foundation is required to pass smog...
New oil, new filter, clean throttle body (they can get really sooted up), clean up pipe, good plugs and wires.
Important: New vacuum lines-especially those linked to EGR system...there can be leaks in old lines that you will not see (trust me). If you suspect EGR, buy a new one...I have a strong feeling this and the related vacuum lines are involved. I would also check the filter on the EGR solenoid to make sure it is not clogged.
A fuel additive, Guaranteed To Pass, can work as extra insurance. I used it, but think the car would have passed without it anyway...I'm sick and tired of smog tests and like to be over-prepared for them.
Finally, get the car hot before the test. Then make sure the technician heats the car to "closed loop," then lets it idle at least for 5 minutes and gets it heated up so the CAT works well.
Don't be discouraged. Be methodical and thorough...you are just getting a machine to run clean. Remember, it has had some time to get dirty.
You will eventually pass. Sure it's frustrating sometimes, and you may have to throw some money at it, but we all go through this and learn what works for our own cars.
Steve
PS Went to school in Berkeley...please give my regards to the beauteous bay! And, toss down an Irish coffee or two at the Buena Vista for me.
engines make most hp at 4-5% CO - before the cat (which makes me suspect a faulty cat). note that wbo2 readings aren't a clear indicator of best power.
optimum timing puts HC below 1000 ppm.
the best all around afr for all emissions is 14.7:1. you can go a little leaner - lower hc and co but raise nox - and add more egr.
as was said before, a working egr will lower nox.
ethanol (e-85) will lower all tailpipe emissions.
turbos work by extracting exhaust heat...leaving less to warm the cat. leaving the wastegate open will help...as well as not making more hp = less fuel = fewer emissions...if your tuning will allow.
i learned something too...i may go for that 3rd gen 3 way cat
optimum timing puts HC below 1000 ppm.
the best all around afr for all emissions is 14.7:1. you can go a little leaner - lower hc and co but raise nox - and add more egr.
as was said before, a working egr will lower nox.
ethanol (e-85) will lower all tailpipe emissions.
turbos work by extracting exhaust heat...leaving less to warm the cat. leaving the wastegate open will help...as well as not making more hp = less fuel = fewer emissions...if your tuning will allow.
i learned something too...i may go for that 3rd gen 3 way cat
