Hey everyone...so over the past year I have had a code thrown about 4 or 5 times. I have used my Gryphon to read it, and it has always been System Too Rich (Bank 1) , which I if I remember correctly is P0172. Well after reading up on the issue with the Fuel Injectors in the 2005 5.4, I decided that I needed to go into the dealer and have this checked out to make sure that one of my injectors wasn't leaking or something. Well, they just called me and said that the problem is not with the injectors but with my Mass Air Flow Sensor. They are telling me that it is stuck open, and needs replacing. Est. Cost - $392.00
#1. I told them DO NOT continue with replacing that, as I would do it myself.
#2. Does this sound right? Could the sensor be causing this code? I do have a K&N intake.

Thanks for any help!

 

Have you ever cleaned the MAF? They make an aerosol cleaner to do that. I'd try that before spending $392.00. I can't imagine the MAF sensor is that expensive, but I have no idea what labor charges and diagnostic time they have in that estimate. This is nothing to change or clean. The sensor itself is a small wire that when dirty can give false readings. It is a critical component of the EFI and can cause all sorts of issues. Unless your programmer is calibrated to the intake, that could be causing some issues too, but not likely rich issues.

 

I thought it was electronic, how would it stick open?
Giving false readings, yeah bit not "stuck open"
Try cleaning it. Like ^ said, I would try to clean it first before I done anything major.

 

Oiled air filters can foul the MAF and cause exactly that. It may be too late to clean it and it may have to be replaced.

OEM Motorcraft MAF at rockauto.com is 130 bucks plus a $35 core charge.

 

And those K&N filters are famous for it. I have to clean the MAF on my Mustang about once a week when the filter is newly cleaned and oiled. At least the old (pre OBD II) MAFs clean up fairly easy - I don't know about the later ones.

 

Agreed, if not corrected for with tunes you would be running lean.

 

I personally have never cleaned the sensor, and no shop has ever either, as far as I know. I had a K&N system in my previous truck, and put one in my current truck almost 5 years ago. That is a total of about 10 years experience for me in cleaning and re-oiling the K&N filter. I am always very careful NOT to over oil. Just enough to get the media pinkish/red, and not white. I have NEVER in 10 years had any issues until last year, which was right around the time that I got my Gryphon. I did tell Corey and those at PHP that I had the K&N system, and it was taken into account when creating my custom tunes. The truck runs perfectly fine, even when the code is thrown. And the code isn't thrown very often at all. Like once in 3 months or so. Like I said, about 4/5 times over the past year. I am not convinced that I have a MAF problem. The tech at the dealer sat there and told me that the "book", says to start with replacing this sensor when the P0172 code is thrown. I really just wanted my dang injectors checked, but they just blew that off. The tech claimed that the sensor is off whack causing an incorrect mixture of air and fuel. But I say, the code isn't constantly thrown, and the truck runs great (no rough idle or anything).?.? I guess I could try cleaning it...because that can't hurt. Hopefully there is a How-To. I am suspicious of my Gryphon causing this though....

 

bump any more input? Much appreciated!

 

Many tuners will recommend replacing your upstream O2's after 50k miles. I have been having similar issues and will be replacing my O2's as soon as the temperature gets out of the single digits.

If it works I will let you know.

Kev

 

It is very easy and inexpensive to clean the MAF. It should be done as part of regular maintenance much like changing the fuel filter. Even it it is not causing your particular problem, I guarantee it will make your truck idle better and run smoother. Look in the index of the Articles and How To for complete instructions.

 

So, I started with cleaning the MAF and no change. I did not see a change in idle or the way my truck ran at all. Code was still being thrown, and more often now. So I ended up finding a brand new MAF on Ebay for $30. I got it installed, and the truck did seem to run a little smoother then. (But just A LITTLE). Everything seemed great, and I thought this issue was resolved. Then last night. The engine light came on again, and its the same code. System too Rich Bank 1. WTF? It seems that the code is thrown more often in this colder weather. During warm weather 75 + I would rarely ever see the light, but now that it is constantly under 50 and into the 20s quite often, I am seeing this p0172 more and more

 

Why won't they check the injectors? Must be morons. The 05 5.4's are notorious for injector problems (trust me, I know), so much that they extended the warranty on them. See my sig, 07M08 link, I've had to use the program.

BTW I have been running a K/N drop-in for about 90,000 un-fouled MAF miles.

 

I don't know. I specifically wanted my injectors checked. I guess telling them about the code screwed me. Because they just looked in a little book that says the first step is to change the MAF. I took my letter Ford sent about the extended injector warranty when I went in, but it seemed to be disregarded. I have had good experience with this dealership in the past, but this has and continues to **** me off.

 

That's crazy. It's as if they brush off doing a warranty repair. Maybe you should call Ford customer service and discuss.