Hi,
The CEL light came on in my 02 WRX today while out for a drive.
The car was driving fine, and then started to idle quite "lumpy" and seeming like it wanted to stall while at tick over. I turned the car off for about 30mins and when I restarted the car the idle was still lumpy and the CEL light had come on.
Driving home the car seemed fine when driving, but wanted to stall and was very rough and uneven at tick over.

When I got home I checked the codes; P0301, P0303, and P0171.
Misfire cylinder 1, misfire cylinder 3, and bank 1 too lean.

Does anyone have any suggestions where to start looking to sort this problem? Or am I better off trying to get it to a specialist to sort out the problem?

Thanks

Chris