ECM Problem

[doug_20]

I'm working on my buddy's '91 Z28 5.7 Automatic. The engine light is always on. I've disconnected the battery and let it sit and right after startup the engine light is on.
So I hooked a scanner up and it just says "vehicle not responding". It's supposed to do just about all cars so I hooked it to mine and it worked fine so I know it's not the scanner.
I tried to jumper the AB pins on the ALDL to cause the engine light to flash the codes, but that doesn't work either. So I think it's in limp mode. Does that sound right??
So then he just orders a new remanufactured ECM from GM. It doesn't come with the memcal chip. So I take the old one out of the old ECM which is a Hypertech chipset dated 1995. I hook all that up and it's doing the same thing all over again.
Could it be the hypertech chipset gone bad?
Is there a way to test it with a meter?
He's going to buy one but I'd rather determine that that's what the problem is before he spends $400 on the Jet six-pack chip that he wants.
I think there's a problem with it, cause it runs super rich. If you're within 50ft of it in any direction while it's running, it will choke you and burn your eyes.

[doug_20]

Got it fixed. Changed the chip out and runs better than ever and NO engine light.