A couple of points - if the EZL "isn't working" there will likely be no spark. Vacuum advance is only applied at light to medium load and has no effect at high load. No vacuum advance will increase fuel consumption, but decrease emissions.

The rate of advance with revs is controlled by the R16/1 resistor. OE is 750 ohms on US models. Removing the resistor will increase the rate of advance with RPM and improve low end torque.

Shorting the R16/1 resistor connector will yield the slowest rate a above advance, which will further reduce emissions, but the car can barely get out of its own way below 2000 revs. This may not be that noticeable with automatics, but it definitely is with a manual transmission.

If you are having problems passing emission tests with a M103 block the vacuum advance signal line and short the R16/1 resistor plug

Duke