Not a ford question, but a general engine question. My uncle has an 86 s-10 blazer with a 2.8L v6. If you stick your finger on the dip stick tube to the engine, there is a strong vacuum. The vacuum is so much, that after the engine runs for a few seconds, you can hear a whistle sound where the engine is sucking air somewhere it shouldn't. Any ideas what could cause this??? Thanks for any help!!

 

Now that's really POSITIVE Crankcase Ventilation.

Check to see if there was any kind of vacuum restrictor on the PCV line to limit PCV vacuum. Check the PCV valve for proper operation.

Steve

 

We put a new pcv in and it is just a hose from the pcv to the TB.