I am in search of some advise in regards to the problems I'm having with my '06 trailblazer EXT LS 4.2L i6, 197,xxx miles. first off, the engine light is on all the time. The fuel gauge isn't working, on E all the time, I had the fuel gauge sending unit replaced on the original fuel pump (much less costly than a complete fuel pump replacement). It worked for about a month and is now on empty all the time again. I wonder if that could be one of the things contributing to the engine light staying on all the time? I've also found different OBDII codes and replaced camshaft position sensor, cleaned the Camshaft Actuator Solenoid Valve, cleaned the throttle body, changed oil & filter, replaced air filter, replaced spark plugs, replaced the heater resister because fan would only operate on the 1st 3 speeds (found wire harness burnt to a crisp ended up replacing plug with pigtail wires along with it), replaced windshield/signal switch, the windshield wiper motor, the drivers side power window controls in the door were replaced trough a recall after burning up (literally). After all of that, and clearing all the codes the engine light came back on & continues to stay on. Now I am noticing that when I start it each morning it has a very erratic idol, tach. jumping from 200 to 1800 rpms, revving up and down quickly and sometimes stalling out on the down side of the rpms. it did this a few times previously but after cleaning the throttle body it quit. That was only a few months ago, could it become that dirty in such a short time? Also I am now hearing a loud knocking noise coming from the rear passenger side of the vehicle at start up, it only last for about a min or two, wondering what that could be. Also, now the light behind the temp. control slide bar for the drivers is no longer illuminated but the one on the passenger side is illuminated. Also, just the other day after starting the vehicle the ABS, Stabilitrac, 4x4 service lights came on and "of course" the engine light was on anyway. it stayed that way until reaching my destination some 22 miles to my work. however, when leaving work 8 hrs later they did not come back on. After all this I wonder if replacing the complete pcm with (maybe) more recent software updates would correct all the electronic issues causing the engine light to come on and even improve the running performance of the engine? If so where or is it even possible to purchase a "plug & play" pcm that would require no programing after the installation?
This thing is driving me nuts!
Any help would be greatly appreciated.
Thanks in advance