Erratic Idle revs from cold start

[DressedToKill]

Car is 08 Vectra 1.8 vvt

Problem started a few days ago. Starting the car after a few hours of non use, revs start to bounce up and down between 800-1200rpm, and seems to judder at lower speeds. After getting up to temp problem seems to disappear and drives fine.

I'm absolutely clueless so don't have a clue where to start. Friend suggested that it could be an issue with a temp sensor or thermostat.

[GreenV8S]

DressedToKill said:

I'm absolutely clueless so don't have a clue where to start.

What are you trying to achieve here?

If you hope to diagnose and fix the problem yourself, that is probably not realistic for somebody clueless.

If you plan to take it to a professional to fix, that is a sensible option, probably won't be expensive, and doesn't require you to diagnose the problem yourself.