New User with a strange problem.
 

Ok then, theres alot of wacky things going on with my 01 Blazer, and Ive spent alot of cash just trying to get it inspectable..

Here are the list of issues, first Im reading a P0300 misfire code, Cyl 1 is misfireing like crazy, with cyl 3&5 not far behind, 2,4,and 6 seem to be fine.
When hooked to a scanner--the scan tool says the truck is in 4wd, mechanically it really isnt, it says my intake temp is -40 yes, negative, it says my coolent temp is also -40, while the cluster maintains that its at 210.
Its also pulling a code for the o2 sensor on bank 1, prob due to the 1,3,5 misfires.
A small backlight is staying on inside the dash cluster, slowly draining power,
Im starting to think all of these issues could be from a bad computer..

Now, the things Ive done.
Ive changed out the cluster already, same prob goes on. all cyl have been pressure tested, new cap, rotor, wires, plugs. new spider... I just dont know what to do next, I fear getting a comp. and programming in, and spending a couple hundred and its something else! Help!! Thoughts?

the drain sounds like a bad ignition switch. but all else put on the brakes, priority 1 is that -40 that means those sensors are unplugged or dead shorted, this will make problems big time! the iat is common to be left unplugged. now 1 bank missfireing can be alot, but a bad front 02 sensor will do this. u gota resolve the 2 temp sensors first, make sure u r running before enableing data stream on the scan tool or data may not update properly. those 02 sensors can short internally too, its a long shot but unplug the one reporting problems and see if other 2 sensors come back. keep us posted im curious now lol.

That's one thing I did forget to mention, the ignition switch was changed out when I I changed out the last instrument cluster. Ill try your other suggestions this week, Thanks!

ok, on the switch make sure ur not a tooth off, will leave stuff on and run batt down. back gate glass not latching and sun visor mirror lights seem to be common to cause draws on these too