Hey everyone,

I was wondering if anyone can help me figure out what's wrong with my car. I have an 06 WRX and cannot pass smog to save my life. I was originally running an aftermarket TBE with a high flow cat and a larger TMIC running a Cobb OTS stage 2 map. I failed on CO emissions with a value of 2.7 under 2500rpm (I was expecting to fail since I was running rich). So using the free retest, I resmogged my car with a stock STi TBE and reflashed the ECU to stock (but still with a larger TMIC) and had a CO value of 3.3 under 2500 rpm.

I passed everything else and was fine under idle. I checked the front O2 sensor and it seemed to be running properly and I don't have any CELs. What could be causing the high CO? Would a larger TMIC cause the car to run rich even when not in boost? (and if so, does anyone have an 06-07 wrx tmic they don't need?) Any advice would be greatly appreciated

 

The stock DP should help scrub you down under that are you coming into the test with hot cats????

Try running like 3 gallons of e-85, and then have the tester run the car at like 4500 rpm for a few mins prior to the test.

If that doesnt work it sounds like you have other problems. Also change your oil prior to the test.

 

How many miles are on your original DP and where was it stored? Did you ever have a blown head gasket while it was on? Before testing you want to run the **** out of it and get it nice and hot. Also don't let them shut it off before the test, keep it idling. I always go to high volume smog shop so they just run it through asap while its hot. I always put the highest octane gas available, change the oil and make sure the airfilter's clean before smogging.

Higher CO's are usually a symptom of running too rich or ineffective catalyst. Check out this link and it'll let you know how you're running based on lambda calculations.

Lambda

 

I bought a STi turbo back from a member off of nasioc, he said that he pulled the exhaust with about 6,000 miles on it. I don't know how he stored it though. Talking to the smog guy, he said that it seems like the cats are working fine. I haven't had a blown head gasket, but I'll check tomorrow to see if that's the case.

From today, I got a lambda of .905 and a A/F of 13.31. If I can't figure out what's wrong, next time I'll do what you recommended before smogging. I had my car idle for 10 minutes to reset the drive cycle, then drove it 20 miles to the smog place, but I didn't drive it hard and it sat in the cold for probably 20 minutes before being smogged. Oil was changed on Saturday, and the air filter looked fine. Could the problem be caused by an intake leak? I removed the air box to get to the O2 sensor the other day, but maybe the box wasn't sitting properly on the snorkel when I went to smog

 

So you're definitely running rich, another thing you can try before the smog is disconnecting the battery and leaving it off for (I forget how long but 5 minutes is safe) to reset the computer and let it relearn without the TBE and stuff.

Though I think a reflash should have given you a fresh start, but worth a try.

Reason I asked about the blown head gasket is when you have a blown head gasket the moisture in the exhaust (if its run for a while like that) will eat the inside of the cat out, I don't think you currently have one.

 

run a gallon of E85 when you go back too.