So, I love my Expy but the wife is starting to get frustrated with putting money into it. about a month ago we had the local shop cut all four cats off, weld up two new fronts and delete the two rears as well as change all four O2 sensors. It ran amazing and still seems to be but this morning the engine light was on with a single P2198 code stored. I'm not sure what to check exactly with just the one code thrown. It seems to be running fine. I also replaced the number 4 CoP around that time too as it was probably not firing at all but i didn't think to check the plug for some reason. I'm thinking maybe start with the plug but was just seeing if any of the wise sages here had any other suggestions before i spend the day on that ridiculous number 4 plug. Thanks and 73