Vacuum help please

[boosted231]

I am trying to run down some vacuum leaks and I have a few questions. When I apply vacuum to the large nipple on the egr solenoid and hold my finger in the back where the filter goes, the solenoid does not hold vacuum. Am I supposed to leave the little nipple open?
The large round ball attached to the charcol cannister will not hold vacuum either when I attach vacuum to the nipple, does this indicate that it is bad?
How do you check the vacuum solenoid on the charcol cannister, I have removed it but not sure how to check if it is bad. Both vacuum check valves going to both the cannister and eger solenoid were bad and I ordered from GM. Thanks

 

[boosted231]

TTT, anyone?

 

[flattype]

I would like to know also

 

[boosted231]

ttt please anyone

 

[gofstbuick]

For the EGR solenoid, Remove the cover from the filter and remove the filter. With the engine running, put your finger over the port (that you removed the filter form) and the engine should die or run very rough. That is because full vacuum is applied to the EGR valve at idle. The purge solenoid has two wires attached. One is hot all the time. The one that is not, the computer completes ground. So, apply 12v to the pin that is hot all the time and apply ground to the other pin (on the actual solenoid) and see if it restricts vacuum or allows flow. I think it allows flow when the ground is completed and all other times it restricts flow.