1984 Chevy Blazer Where do I find a new computer?

The full sized Blazers used the same computer as a similar equipped full sized truck. The difference is in the PROM chip inside. In your case it almost sounds like it is the Cal-Pak (PROM) that is the problem. Shouldn't be hard to find a used computer and you could buy a chip for it from many online places.

Thanks for the tip. It is the PROM Chip I bought a computer but used the same chip and it did not fix the problem. I am now looking for the chip. because the car is four wheel drive manual transmission the chip is hard to find. Thank you for the tip on the chip

Parts For Less in Tuscon shows one that should work. It's from a 1/2 ton Chevy truck, with the 350 and a manual trans. 50 bucks. Phone is 1-800-571-7899
Call them and see what they say.
Being a 94 you should be able to buy an after market chip for it as well, and GM does still sell them but the price isn't nice.

Thanks for the infor. I called them and they have the computer but not the chip. I found somepne that can make a new chip but I dod not have the broadcast code. Called Chevy, what a waste of time, and they have no idea. I had to explain to their customer service guy what the code was. Anyway do you have any ideas how to get the code? It is a 1994 full size blazer, $WD TBI with a 5.7 and manual 5 speed transmission. PS GM does not make them anymore.

The last PROM I needed I bought from the parts counter at the local dealer. But it's been a while since they seldom fail. can make you a new PROM
Jet Performance or Hypertech may also have something that would work.