Guys, I have a '99 w/ a 3.4 thats had a intermitent smoking when cranked up. I had a Toyota tech look at it on the side and said it was sludged up and not allowing the oil to drain from the head back into the pan. It was picking up oil and sending it back through the intake causing the smoke. I picked it up since I'll have to wait on the funds. The next day my daughter called and said it was skipping. This time I carried to my brother-in-law who has a shop. He pulled the #3 plug out and checked the compression. About 30psi [:@]Should removing the heads cleaning a servicing fix this? He seems to think the sludge is keeping a valve from closing. I wouldn't want to spend the money if it should be rebuilt . Has about 140k on it now. Sorry for the long post. Thanks