TAJohns, do you have a K& N cold air intake or some other aftermarket intake ? If so, I have read and heard many times that these CAI systems will harm the MAF if they have been over oiled. The excess oil gets on the sensitive MAF internal parts and it destroys these fragile parts. The MAF cannot handle lots of oil.
Do you have any other aftermarket mod's to this engine ?

 

I have a stock air box and a stock ACDelco air filter.

 

I think I noticed something yesterday. I hadn't driven the blazer in a few days and the battery was stone dead. And when I started it, boom that MAF was dead. What I am thinking is that the MAF is somehow staying on and getting cooked while killing the battery. Of Course, once again I have to order a new one. I think while I wait for that I am going to dig into the wire harness to see if I can find any damage. The other thing I want to test is now that i have it disconnected I want to let it sit for a while to see if the battery dies. I want to get to a junk yard to look for another harness but they all close early and i have to work every weekend for the next month. If I can't find anything wrong I may run my own harness that uses a relay to a switched power source so that it will override the old circuit. I also noticed that I keep blowing the fuse for the interior lights, so I wonder if they are related.

 

Maybe wiring fault (shorting of two wires) which keeps the heating element energized even with key-off?
Or whole ECU still getting power?

 

That's a good question. I have had the MAF unplugged since Friday and it just fired right up with a full battery. What is odd is that the MAFs last for about a week or 2 and then they just die and then the battery is dead. I think I might be digging into the harness this weekend to look for an issue in the wiring. I'm driving this thing to the beach in a few weeks which is about 4 hours so I would like to get this figured out.