My wife has a 05 that she got about 5 years ago. A few years ago the battery went bad due to to much subwoffer use with truck shut off. I pulled the spare (brand new) battery out of my jeep and put in the trailblazer. Ever since then is would stall in the drive thru with the heater or a/c on. I figured it was just to much draw on the electrical system and never did anything about it. Over the last summer while towing our 25' camper it has gotten worse and I started asking other mechanics about it. Being a heavy diesel Mechanic I did not know what it could be but would be dammed if I was going to pay someone to do something I could do my self. I heard many times it could the intake throttle valve due to carbon build up. After watching MAY03LT very well done video on YouTube I removed and cleaned the throttle valve. Thanks to MAY03LT. It was very built up and required the use of a brass brush to clean. I tried a tooth brush like in the video but it didn't work. Once I was done truck idled smother. Now the issue have is when taking off from a stop it misses bad and almost quits. I'm sure it needs new plugs as they haven't been changed since center new and have almost 200000km on them. Found new ones in stock by work and I'm picking them up tomorrow. I also have codes p0410, p0442, p0128, p0014 and p0300. Form what I have read here I'm guessing that the p0300 will be fixed by replacing the plugs. I also know the cooling fan hub is shot but don't have the $500 for a new one right now and suspect the thermostat to be bad as well as the truck takes forever to warm up. I checked for a video on what to do about the code p0410 for the air purifier with no luck and need help and finding the problem. Also have no clue what to do about the other codes. Any help would be great. Thanks again to MAY03LT and everyone else who can help.