Okay, so I've pretty much decided on buying a direct-fit high-flow Catco catalytic converter for my TA since I failed emissions rather miserably about three weeks ago or so.

My HCs were 2.34gpm and need to be below .80, and my CO was 44.6gpm and needs to be below 15.0. This means both were about 2.95-2.97x too high. CO2 was at 588.5gpm, but not compared, and NOx wasn't even read.

Now, I did have some funky problems for the test that day and I do think it was running in limp-home mode (it was when I had begun chip tuning stuff, and something wasn't making complete contact...all fixed now).

For all I know, I could pass with a properly tuned chip now since it was so screwed up the first time.

Anyways, I'm going to buy a new cat and O2 sensor just to make sure, but I also read about someone saying they had an exhaust leak and it was causing spikes in the numbers. My O2 sensor is probably rather old as is my cat (though I found out today it isn't the stock cat as previously thought).

I know I have an exhaust leak because I can hear the ticking. However, it seems to go away once the motor heats up so maybe it isn't leaking enough to make a difference once at temperature...so I guess it may not make a difference.

I just want to get this all fixed so I can start focusing on the new motor and stuff.

I kind of got off topic from what I wanted to start on here. I'm looking at my charts and they seem to be making a bit more sense to me now. I can't tell how fast the car was going (variable speed throughout testing) because there doesn't seem to be a scale for the MPH. Anyways, I noticed that the spikes in the HCs and the CO (separate charts) occur at the exact same times for the most part, with the spikes in the CO chart seemingly to be heavily exaggerated when compared to the HC chart.

For instance, when HCs go to 4gpm, then the CO is at 45gpm. When HC drops to 3gpm, CO drops to 15gpm. It seems that whenever my HCs are at 2gpm or less, my COs are also at the limit of 15gpm or lower. Yet, when the HCs go back up to 3gpm, the CO spikes to just over 60gpm. It appears to be somewhat related to speed as well. In the middle of the test when MPH drops to zero, the HCs come down to the limit and the COs go down to zero.

Its definitely a spikey looking chart, and I'll have to try and scan it in on my other computer (neither scanner works with WinXP).

I'm no emissions expert here and was curious if anyone could understand what I'm saying by what I said above. Maybe someone that deals with emissions all the time

Also, does anyone know if I can go in for a re-test here in IL without having to show I spent money on my car after the first time? Can't I just tell them my car wasn't warmed up properly and was having some issues that have since been straightened out without spending any money? Can't I say like an exhaust manifold bolt was loose or something? It appears that I have to show receipts for spending like $250 to get it fixed before re-testing, but that doesn't sound right to me for just my 2nd time going in. I'd like to go in after school one of these days with a properly-running car to get a new baseline.

 

High HC and CO readings generally indicate a bad or lazy O2 sensor. If you were running with a problem or modified prom you basically answered your own questions. In most states you must show a copy of repairs by a licensed shop, and you usually have up to thirty days for one free test. I put a post here called Tech Tip about using heated O2 sensors. Read it, it may help.