Re: check engine light. code P0171
capnray
10-01-2008, 07:15 PM
My 2002 Ranger started throwing P0171 and P0174. I know from experience with other vehicles that this involves the MAF sensor and vacuum leaks downstream of the MAF. My MAF was clean, so I checked the vacuum lines, all were OK. I then noticed that the PCV system vents directly into the intake at the throttle body. I found a rubber elbow abraded by the upper radiator hose. Autozone does not carry the item, so I decided that 5/8" heater hose would work, however I had none. I found a Pinto breather hose which I modified and that should fix the problem.
The last thing you would suspect is PCV, but any system connected after the MAF must be checked when these codes appear
The last thing you would suspect is PCV, but any system connected after the MAF must be checked when these codes appear
Automotive Network, Inc., Copyright ©2026
