Moved to the Gen2 area. 
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You are 'shotgunning' parts. Do you have a misfire code? Did you use a proper wide-band Lambda (O2) sensor?
If not I'd first clean the throttle body; then clean the Idle Air Control.
If the surging/hopping happens at road speeds, you might need a Throttle Position Sensor. They have been known to go bad.
BUT you might be best off having a pro look at your car. See if the TPS signals are uniform as the throttle travels along its trajectory. And, have and CEL codes read.
Post back with results.
++++++++++
You are 'shotgunning' parts. Do you have a misfire code? Did you use a proper wide-band Lambda (O2) sensor?
If not I'd first clean the throttle body; then clean the Idle Air Control.
If the surging/hopping happens at road speeds, you might need a Throttle Position Sensor. They have been known to go bad.
BUT you might be best off having a pro look at your car. See if the TPS signals are uniform as the throttle travels along its trajectory. And, have and CEL codes read.
Post back with results.
