Final update: passed with flying colors! Granted my car is legal and all, it still failed last time. All I did was drive hard with OD off on the freeway and went straight to the station after. My HC today was 57/84 and 23/49. Even better than two years ago. Hope this thread helps someone in the future.
whats smog? LOL
Your HC's are still somewhat high although granted you did pass. Maybe try wrapping the D/P for next time. The DP is a bare pipe and a larger diameter therefore the exhaust cools at a much faster rate. The R/T cat also has no heat shield to retain it's heat.
passing is such a wonderful feeling!
Passing IS a great feeling. its amazing how something as simple as smog can get stressful...
My final test results:
15mph: CO2 15.1% O2 0% HC 57/84 CO 0.08/.49 NO 20/484
25mph: CO2 15.1% O2 0% HC 23/49 CO 0.03/.46 NO 22/498
What could be causing my heightened HC? and what type of heat wrap would you suggest for the RT dp?
Any aftermarket exhaust wrap installed before the cat will help pre-heat the cat.
I would remove all the carbon crap that builds up in the EGR pipes and behind the throttle body plate. Also using a scour pad, remove the layer of residue that builds up on the coolant temperature sensor.
Hey guys sorry to bring this back from the dead but...I failed smog. Talked to the guy was pretty helpful, said I'd need to run injector cleaners and probably a new cat. More opinions would be nice.
Here's the story. Drove the car around, did a few pulls. Car is still in TTC mode. Still has the original cats with 180XXX miles. Just put in new plugs, new air filter, oil was still clean but unchanged.
Here's the numbers
15mph: CO2 14.1% O2 1.1% HC 52/114 CO 0.49/.19 NO 424/386
25mph: CO2 14.3% O2 0.0% HC 36/36 CO 0.46/.04 NO 711/9
Any help to pass smog would greatly be appreciated!
Do-Luck Floor Support Bar Install
Your NOx numbers are really high. I'd remove the EGR and clean it out.
Also have you done all the good general maintenance? Cleaned TB, replaced pre-cat O2, etc. I like getting all that out of the way first and foremost.
Hrm...didn't try that yet Ryeno...just replaced the pre cat 02 with a borrowed sensor. Done all the general maintenance, only thing I'm failing on is the HC, I'll try to get around to cleaning the EGR and the TB. How do I clean those anyways?
No, your HC's are high... resulting the high (but passing) NO's on the low speed test. Your NO's are low on the high speed test.
What's TTC mode? Any sequential modification is tampering with the stock vacuum hose routing and vacuum conditions. I would check for leaks.
High HC's are generally related to Ignition or Leaks of vacuum from PCV, EGR, Intake Manifold, Throttle body, even leaky intake/exhaust valves.
High CO's are generally related to Fuel or faulty Fuel related part or clogged EGR related part. Your CO's are good... again I would check for leaks.
ok guys reporting back...as of right now...my HC are still too high. Checked for leaks went back to sequential (TTC true twin conversion), put in a brand new cat, as of right now it's looking to be an internal issue...but still going to look into cleaning the EGR and TB just haven't had time. I'll stay posted
Do you currently have rough idle?
it seems like it idles fine; that's the weird thing...the engine runs completely smooth, no hiccups no nothing.
how hard did you run your car before going in for the test? I ran mine pretty hard for a good 10 minutes on a lower gear to get higher RPM and then got straight in to the smog and had the guy test it for me right away. the difference in HC was from 90s to 50s. If you get a free retest, would suggest doing that.
Do you have a boost gauge, boost controller or SAFC that displays vacuum and boost? If so what is your vacuum at idle?
Don't exactly remember the numbers off the top of my head but here's something that's pretty approximate
15mph: CO2 14.7% O2 1.1% HC 52/80 CO 0.49/.19 NO 424/386
25mph: CO2 14.7% O2 0.0% HC 36/20 CO 0.46/.04 NO 711/9