I have a 2000 malibu about 3 weeks ago it started acting stupid. When I turn on the car the fuel and temp gauge wont work along with the power windows and a/c. After driving for 3-10 minutes it will all start working. So I called two shops and they both said it sounded like a key passlock cylinder so I had it replaced. The repair didnt help at all so I took it to another shop and had a diagnostics test done and they said it was coming up with so many codes that they couldnt figure out what was wrong. 3 weeks ago my car ran perfectly and now it has gone crazy anyone got any ideas they would be much appreciated.

Try a new ignition switch, not the key one, the electrical one at the lower column area.

got any intstructions on how to do that online

None I know of. The switch is located under the dash on top of the lower steering column. It has a rod from the key switch, electrical connector and attaching screws. Do to its location it’s not an easy job but with patience it can be done.