I'm feeling a little dejected now. I've been fighting an overheating issue since I got running, and now it also runs like a**. After the initial period where the PCM was learning and figuring stuff out it was obviously a little weird, but once it got past that it was running smooth and strong. Better than it did before I even installed this stuff. Very quickly though I ran into overheating issues and have yet to figure it out. At first the electric water pump popped a fuse, so I upgraded that and I've confirmed I've got voltage at the harness (Meziere HD w/ Innovative wiring harness), but it's driving me nuts. This morning it seemed like it was fine, held a steady temperature, was blowing heat from the vents, and then it acted up again, overheated and was blowing ice cold air out the vents. Every time the expansion tank is leaking, steaming, boiling, and I get nothing but air and steam out of the bleeder on the thermostat. I initially put just over 4 gallons of coolant/water into the system which would be the normal capacity for a complete system drain. For the life of me I can't figure out what's going on. And also at some point today it decided to start running like crap. It idles and runs rough at any RPM, likes it's missing or breaking up all the time. You can feel it in the car almost like a light chugging. I disconnected the battery for awhile, but it made no difference. It may have started after I pulled off the intake tract to get at the water pump harness, and it popped a code for not having the MAF plugged in, but I cleared that code and with it back in and reading values from it, it still runs rough. On top of that I got another car dumped on me today that needed a power steering pump replaced and some other minor stuff, so the Caddy will wait. Not happy anymore.