[CruzeEcoBlueTopaz]

I had a simliar issue last week. My malfunction lamp came on at 101,500 miles. I forget the codes it set off po171 and two others. Also 25 miles down the road my service stabilitrack and traction control lights came on and then went away after turning the car off and on. Anyways I opened the hood and heard an unusual hissing air leak noise as well as some oil around the engine oil filler cap. I was 150 miles away from my dealer so I decided to just drive it home the lamp wasnt flashing. I noticed a rough idle and 300rpm above normal idle. 600rpm is norm for me now it was 900rpm and now it was wanting to stall but after a little throttle was fine. I noticed during low speed cruising it would hesitate for a split second the same feeling I get when my fuel injectors shut off going downhill. Except this was happening randomly.

Finally got it into the dealer and this is what the tech says " 101325 ses light on 2.40 diag found lean code set p0171 due to the pcv valve in valve cover leaking unmetered air into intake replace leaking valve cover and cleared codes road tested no more ses light on at this time thanks."

Basically the valve cover was replaced which included a new pcv valve. This fixed the problem and my cruze is back to normal and averaging 50+ mpg over 300+ miles per day. : )

List of parts

5 CPV < --- I think this was labor because it was 2.5 hrs and $ 245
1-55573747 seal - 22.29
1-55573746 cover - 69.53
1-3308 cso-3 charges 15.72

All total $ 350.00 ouch

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