The VSV should be initial cause and start of the problem. When vacuum is not available or insufficient, it can cause a lot of problem.
This is not Toyota technology alone, almost all other makes have a problem with or are difficult to diagnose emission controls, especially for the earlier pre-Y2K models.
At least we are getting somehwere and the answer should be close.
Please consider a to help us answer more questions.
Wednesday, January 2nd, 2013 AT 11:50 PM