I have a 2011 LT with 87K (out of warranty). There are no mods. I've been researching my issue and have read the TSB on the P1101 code that I can't get to go away. In the past I have replaced the valve cover (PCV issue) and the PCV isn't venting so that seems OK. I took a shot in the dark and replaced the MAF sensor but that isn't it. Indications would be a vacuum leak of some kind. My local shop took a look and couldn't find a leak any where and said the exhaust was fine. The TSB (NHTSA# 10053929) recommends checking the PCV pipe. On my Torque Pro app I have three throttle measurements, absolute throttle and throttle are around 13% but the relative throttle is .4%.at warm idle. I pull the pipe from the intake manifold and cover the hole and the relative throttle pops up (fluctuates) and I get rough running. Should I be replacing the PCV pipe or be looking for something else? Good air cleaner and I can't find any leaky hoses or fittings. Maybe clean the throttle body too? The car actually runs fine but it's time for emissions testing and reg renewal and I need to make this go away.
Mark
Mark