I have a stock 2002 2dr 4.3L v6 Blazer, and I've been having a few problems with it.
When it get it up around 50mph and I go to accelerate, the rmp's drop from 2000 to 1500, then shoot up to almost 3500rmps. I've checked the trany oil, and it's still fine, and I had the engine oil changed not to long ago. I do have to check engine codes coming up, one is a Evaporative Emission Control Leak, and the other is for a coolent flush, but I don't think they would cause the acceleration issue.
Has anyone ever expirenced this issue or something like it?

 

How does the fluid look? Still pink/red, or does it look brownish? Also does it smell burnt at all?

 

What are the exact codes coming up? Z