Hey I had these LTH put in yesterday and am getting a check engine even after tuning the car. The mechanic who installed them told me 2 of the o2 sensors wouldnt fit so he had to put dummies to fill the holes. My air to fuel ratio is 20.0 (doesnt move at all). Is this because the computer is all whacky from the dummies? Or is my air to fuel really that high? My car seems to be running pretty well, but the check engine is going to screw me once inspection rolls around. The guy who did my car wont be in until monday or I wouldve went back already. Anyone know if this is safe to drive with and is just a computer malfunction? The sound is also extremely loud especially on cold start. Didn't expect the headers to make that much of a difference compared to having just the borla s type catback I had alone. Any help is greatly appreciated!