Iv been chasing an issue on my wife's 2007 Toyota Corolla S for a while. It started about a year ago and has been going on ever since. It has plenty of power but it randomly goes into a kind of limp mode. It won't completely stall but the RPM won't get past 2000 or so. Once you slow down almost to a stop it starts to shudder and shortly after it fully stalls. I notice it occurring mostly when coming to a stop but I can't recreate it. It originally threw a code pointing to the ECM and the mechanic agreed so we got it replaced. Through that same line of thinking several other thing were replaced such as: both O2 sensors, both catalytic converters, plugs, and ignition coils. All other maintenance has been done regularly. The only other factor may be that we did use a Snap Shot device that was supposed to monitor our driving habits in hopes for lower insurance rates, but I have no way of knowing wether it had any influence on the issue. The device has been disconnected for several months now. Any input would be awesome!