Does this EEC act in a similar fashion to the EGR?

Here’s why:

With the pipe (containing the purge valve) connected then the engine will not hold idle revs, if it does hold them the engine is bumping/hunting dramatically.

With the pipe detached the engine is lumpy.

If you reduce the intake by half (varying by using finger) the idle is perfect.

Therefore the question is: If the purge valve is not working correctly (not doing as the ECU says, will this give the same symptoms as a faulty EGR.

1.8, 02, club
(EGR blanked)