I just had a very strange thing happen to me. I was getting a CEL after I removed all three cats from my car and kept the stock exhaust. This light came on every 3/4 of a tank of gas and would stay on for about 50 miles or so. Now I have upgraded (a couple of weeks ago) to an Apex-i N1 Exhaust and haven't had a check engine light since. Anyone care to try and explain how/why that would happen? Is it possible the stock exhaust is so restrictive that it messed with the O2 sensor and triggered a CEL (I am positive that it is the O2 sensor that caused the CEL, had a scan tool analyze that)? Anyone else have anything like this happen to them?
CAS