A hose that is part of my K&N Typhoon air intake system came loose,no doubt causing the P0171 AND P0174 codes and my Service Engine Soon light to come on. I tightened it yet the Service Engine Soon light is still on.

I understand that perhaps my Mass Air FLow Sensor is dirty or the DPFE sensor needs replacing. Can someone in simple,easy to understand language please tell me how to locate and clean the Mass Air Flow Sensor and how to locate The DPFE sensor?

thanks in advance
Mike Long
Addison Tx

 

Your mass air sensorare the two tiny wires inside the part right next to your filter housing. It has a plug going into it. Just unhook it from your filter housing, pull it up enough to see the two sensors, and spray throttle body cleaner directly on them. Use the straw that comes with the bottle of cleaner to direct the cleaner onto the sensor wires. I had to do this and my tuner suggested this technique-it worked for me. I used STP throttle body cleaner (also known as carb cleaner) from Advance Auto. I have no idea what or where the DPFE sensor is, but my KN filter caused my CEL to come on because the filter was over-oiled, resulting in filter oil getting on the MAF sensor wires. It will take at least 200 miles before your CEL turns off unless you unhook your battery for a few minutes (10+mins preferably). Hope this helps some.

 

Many thanks Sir! i do believe I've located it. So I unplug the plug, or unscrew the two screws(odd looking screws they are
) on the external surface of the box to which the plug is plugged into?


Mike

 

You can just open your filter holder,and pull up on the intake tubeif you want and spray it from there. Just don't touch the sensors, they are very sensitive.

 

The DPFE is the Differential Pressure Feedback EGR sensor. It's on the back of a steel bracket just aft of the EGR valve, and has two hose connected to it from the bottom and an electrical connector on the inboard rear. It monitors the EGR flow rate and if clogged or malfunctioning it can cause the engine to run lean as there will be too much recirculated exhaust gas; or recirculated gas when there shouldn't be any.[/align][/align]You can view the diagnostic tips for P0171 and P0174 here...[/align][/align][/align]