To recalibrate the e-gas:
Disconnect your battery for around 15-20 minutes so the computer can drop learned values.
Reconnect battery.
Turn key to on position for 1 minute. Do not start engine... do not touch throttle.
Turn key off for at least 10 seconds.
Start car let it idle for a few minutes to relearn idle fuel map.
take car for a test drive and see if it changed anything.
For vacuum testing go to the thread titled Car Dies go to post #50 on page three
look at the hose marked with the yellow yes you want to tee your vacuum gauge in where it meets the intake just before the resonance flapper.
Let me know how you go
Was I correct?? Do you call idle tick over??
Damn I almost forgot these cars do not do well with after market MAF sensors.
The only brand you want to use is a Bosch. (Porsche MAF sensors are rebranded Bosch)