Contour Enthusiasts Group Archives Forums General Troubleshooting Rough Idle again!

I posted a month or two ago with the problem of very rough idle, only when very cold (below 30 degrees). At that time I had both PO174 and PO171 codes. I was thinking a vacuum leak, but sprayed around and could not find one. I decided to replace the TSS because in the summer I felt I should have. After replacing the TSS the problem seemed to go away. Of course since then it has not been extreamly cold. Until this week. Monday the rough idle came back. It only idles rough in park. If I keep reving the engine long enough the car will not die, but will end up idling very low around 500 or so. Once out of Park and in gear it idles fine. Yesterday I finally got a CEL and it came up with only one lean code PO174. Do you still think this is a vacuum leak? Even though I sprayed carb cleaner around on the vacuum lines and connections and found nothing? If so I guess I will take it to the shop and hope they can find it instead.

Thanks for any info and sorry to bother you with this problem.