There can be a lot of different causes for your OBDII DTC P0174, because your Ford PCM uses so many sensors and references to help operate the engine. The check engine code of P0174 is a code for your Ford Flex that signifies that one side of the engine is running lean. In this case it’s Bank 2 or the side of your 3.5 liter engine that’s closest to the firewall.
Usually when this trouble code is triggered, lighting off your Malfunction Indicator Lamp (MIL), it’s caused by intake leaks. Before you undertake the project of learning how to replace a Ford Flex MAF, check your intake and intake snorkel for signs of any leaks or cracking. If you have managed to diagnose your Mass Air Flow (MAF) sensor, you will need to replace your Ford Flex MAF and that’s what our DIY How To is for.
Today we’ll be showing you how to resolve and eliminate the OBDII trouble code of P0174 as well as P0171 as it relates to your Mass Air Flow (MAF) sensor. This Flex truck carries a VIN number ID of 8 and the identification of the VIN is 42447.
To begin our How To Replace a Ford Flex MAF guide, open your hood and locate your air intake and MAF housing.
The Ford Flex mass air flow sensor is mounted to the intake snorkel and part of your intake housing. Because the two screws that hold the MAF sensor in place is hard to reach in a stock location, we’ll be removing the MAF housing first.
The part number for this particular mass air flow sensor is Ford BR3Z-12B5-79-A and it can also be found as a Lincoln MAF under part number BR3Z-12B5-79-A1.
First you’ll need to free the intake pipe and the intake system of all sensors and electrical connectors. Unplug the MAF sensor as well as the two pin weatherproof connector that’s near your throttle body.
When you are replacing your Ford Flex MAF sensor, there’s three distinct components of your intake system. The air box which your MAF bolts and mounts to, the accordion like snorkel pipe and the MAF sensor itself.
You will need to undo the clamps that hold the snorkel pipe in place, start with the worm clamp near the throttle body.
Now loosen the hose clamp that runs into your airbox and MAF housing.
Now that these two clamps have been loosened, you can remove the snorkel. Now you should have the airbox standing alone in your Ford Flex engine bay. Undo the clamps that hold the top part of the air box, there’s four total.
Now that you have all these clamps undone, the top half of your airbox as well as the MAF can be removed. Unplug your MAF and unscrew the two bolts that hold it in. You will be replacing your old MAF with the new one, and using a scanner or scan tool to clear your P0174 OBDII trouble code.
That does it for our How To Replace a Ford Flex MAF article, if you have any questions or comments regarding this DIY article or the OBDII DTC P0174 or P0171, please leave them below!
will this toubleshooting work on a 1999 xk-8 jaguar/ with dtc code po171-174 ?
Hi Dave, okay so it sounds like your Jaguar is running lean, which can really vary. Unfortunately it’s probably more than just the MAF sensor, although your Jaguar is equipped with a different engine than the one shown here. I would suggest starting with your front or upstream 02 sensors first sir. Thanks for commenting! Let us know how it turns out!