1999 GMC Sierra V8 Four Wheel Drive Automatic 92,000 miles
When I start my truck in the cold it idels rough and dies untill it gets warm. The service engine light came on after that. The codes are PO171 Left bank runing lean. The other code is PO174 Right bank lean. I check the internet and found most of the sites suggest to clean the mass air flow sensor and replace the fuel filter. I bought that mass air flow senser cleaner, a bottle of fuel system cleaner, a fuel filter, and air filter. Replaced the iteams and cleared the codes. The next couple days it was around 50 degrees outside and everything ran fine. After a couple of days it got cold around 20 degrees. The truck was hard to start again and the codes are back. What dou you think. Should I replace the mass air flow sensor or is it something else. Thanks for any help you can give me. Mike
have the same problem?
Thursday, February 7th, 2008 AT 3:16 PM