my 4 runner is blowing white/blue smoke when I first start it up. any suggestions. I pretty sure I have an engine sludge problem. What do I need to do to fix it?

 

Sounds like maybe a bad head gasket. If it has overheated in the recent past it may have wrecked the head gasket. Check for coolant/water in your oil. It might even look like coffee with cream in it in bad cases. Check if it is consuming either oil or coolant, or both. You need to figure out what you're burning and then find out what the cause is.

 

My 99 did the same thing for a few years and finally died of engine sludge. We just now replaced the engine.