When testing an EGR valve with a vacuum pump, should the valve hold a vacuum?? Mine actuates when vac is applied, but within a couple of seconds, the vac bleeds off. I'm thinking it is supposed to hold a vacuum, but want to make sure before I go out and buy another one. (The vac pump and the hose were verified not to be leaking)

Also, where does the EGR vac solenoid mount??

Thx!

 

Presuming this is on your '87 TPI conversion, the EGR valve is a negative backpressure design:



There is a pilot valve within the EGR that will bleed off the main vacuum source unless there is a slight pressure differential across the two valve ports. Testing with a handheld vacuum pump may not yield the results you expect.

 

You can try this to help diagnose the possible valve problem:

 

Thx for the reply Vader!!
Yes, the EGR valve in question is for my 87 TPI eng.

Currently, the eng is on the eng stand, so I can't use the flow chart.
I was wanting to confirm the egr valve ops before I installed the runners and plenum and save myself the expense of having to buy a new set of gaskets for the Hi-Flow runners ($$$) if it does need replacement.

Anyone have a pic handy of the EGR valve vac solenoid mounting??