System lean in bank 1 - P0171

Hello,

In the diagrams down below I have included the factory diagnostic troubleshooting guide for Direct Trouble Code (DTC) P0171. I see no listing for DTC P1133 listed for your vehicle. If you double check the DTC number for me I will be happy to look it up for you. The guide for DTC P0171 is pretty straight forward. I would definitely check for vacuum leaks. By vacuum leaks, what I mean is any unmetered, or any air leaking into the intake air system after the Mass Air Flow sensor (MAF). A good way to do this is to get a propane torch and crack it open on the lowest setting, making sure not to light it. You just want the propane coming out of it. With the engine running, run the propane torch along the air intake duct, throttle body, intake manifold, vacuum hoses, EVAP hoses, paying special attention to Positive Crankcase Ventilation hoses, EGR inlet, and the intake manifold, both inside the valley and outside. Anywhere there is a leak when the torch passes by it the engine rpm's will pick up as the propane will get sucked into the system. This will take care of this DTC. I have also included a link below for you to go to:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Please get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

Hello Warren! I have worked at a Ford dealer for over 27 years and can tell you with confidence that the intake gaskets will need to be replaced. We usually replace the top portion because the baffles come apart inside and rattle, (it has a two piece upper intake) and replace the gaskets on the lower portion. This is the main culprit for a p0171, p0174 codes.

That is the nature of the beast with vacuum leaks, especially with rubber seals or hoses, the leak is never the same day to day. Keep us posted after those gaskets are replaced! This is a must if they have never been replaced! I’m glad you enjoy the site! Cheers

Hello again,

If your vehicle is running fine, then I wouldn't mess with it. The DTC will keep your MIL or "check engine" light illuminated until it is erased from the PCM. There are to ways to do this. The first is to take your negative battery off the battery for 5 minutes or longer. This will completely erase your PCM's entire Keep Alive Memory, including all learned values and your vehicle will be starting from scratch. The second and the more highly recommended method, is to hook up a code reader to the Data Link Connector (DLC) and erase the DTC that way. Either way please keep us informed as to your vehicle's progress.

Thanks,
Alex
2CarPros

Hello again,

It might cause the MIL to illuminate with an ABS DTC. The only way to know for sure is to get a code reader and pull the code(s). This will also allow you to erase the DTC(s) when the problem(s) are fixed. Here is a link below with how to pull the DTC(s) if you are unfamiliar with how to do this.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Please go through this guide, if necessary, and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

A wheel cylinder leak will not cause a mil light to turn on, specifically an ABS light. And clearing the code will be like brushing dirt under a rug. As the vehicle is running lean the PCM is adding fuel to compensate so your fuel economy will suffer for sure! The vehicle may run “fine”, but over time this is not good for the engine. I used to get a lot of these at my dealership because most techs don’t want to do the work. I would shop around at other shops, specifically Ford specialty shops. Not trying to step on any toes, just my opinion.

BMDOUBLE is one of our best! Please let us know what you find. We are interested to see what it is.

Please let us know what happens.

Good deal! Thanks for the update Warren!

Correct, connect it to the main vacuum feed to the intake manifold which goes to the brake booster. Let us know what happens.

Please let us know what you find. We are interested to see what it is.