So looseNut posted a really nice list on page one.I don't think that this has been mentioned as a little list.
Before you start pulling your hair out trying to get one of these cars running correctly be sure to cover your basics.
New spark plugs Bosch W6DP0 only, don't even ask
New Bosch cap and rotor
New plug wires
New fuel filter
Replace all vacuum lines with oem cloth material in the correct size, 1M to ecu. Use mini clamps or zip ties on all connections.
Check and tighten all of the IC boost tubes and connections.
I always like to replace the #30 power control relay under the dash for the ecu. This part is not supposed to go bad, I've seen them cause intermittent issues.
Now lets go back to LooseNuts list, ok here it is
I think a FAQ should be precluded with a section titled
"So you just bought a G60 Corrado, this is what you do first."
1. Change/test battery
2. Change/test alternator or voltage regulator
3. Replace battery wires with thick ones. Clean up connections.
4. Clean up all ECU grounds. Relocate that one ground to the TB.
5. Replace all vacuum hoses. ECU hose is of a critical 1 meter length.
6. Replace blue coolant temp sensor. (it's cheap) If gauge is not working, replace black sensor too.
7. Test throttle switches with a multimeter.
8. Test resistance of the injectors and harness.
9. Return ignition time to STOCK specs for at least 6 months. The character of the G60 changes everyday and you need to be familiar with it before you decide to melt a piston (happens to the best of us.)
Besides, it will only be running for 3 months during this time.
10. Do not even look at performance parts for 8 months.
11. Invest in a good air filter!
12. Tighten all IC hose connections.
13. Install an air fuel gauge Learn the difference between open and closed loop.
14. Clean TB and ISV with carb cleaner (or whatever works for you)
15. Replace the O-ring on the idle adjustment screw. Don't be afraid to remove the screw and get a good look at it.
16. Fix all broken wires from the O2 sensor all the way past the first connection/harness. Ensure the O2 sensor ground wire is clean and strong.
Something like that and then more expensive items can be tracked down in the FAQ. Like if a/f gauge isn't cycling - replace O2 sensor.
Feel free to add more to the list.