i drive an o5 zx3 and about a week ago it started dying sometimes in idle. a couple days later check engine light came on as po171, the guy who pulled the cpde told me it was either an air sensor or my spark plugs, after doing some reading it looks like the problem could range from a dirty MAF to an air leak in my air filter. basically i just dont have the funds to invest in a big search, any suggestions on tracking down the problem?