Poor Performance

WARNING: This page is about a different car, the 1995 Volkswagen Passat. However, it is still accessible from the selected car via links, so may be relevant.

Check fuel pump.
Check throttle cable adjustment.
Check auxiliary air intake system.
Check MAF sensor lever adjustment and control plunger.
Check TP sensor.
Check fuel system differential and residual pressures.
Check injector fuel pressure and volume.
Check full throttle switch.
Check intake air preheating system.
Check catalytic converter.
Check ignition timing.