If you have the ability to look at fuel trims, it will help in this diagnosis.
P0171 and P0174
- Thread starter NavyVet88
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Originally Posted by NavyVet88
Thank you guys for your help. I'll post the results of what was found when I find out from the mechanic.
You know what Murphys law says right?.. the one time you don't have time to rip into it and have to take it in... it's gonna be something stupid simple, just watch. Never fails..oh well. As long as you took it to a competent shop they'll find the cause. The "hard" work on FT trouble codes is just doing the diagnosing. I went through something similar just recently, it's turning out that I got some bad gas blocking flow. My LTFT's were double digits recently after picking up some questionable fuel... I'm I the process of cleaning out the system and now my FT's are returning to near normal levels of around 6 and 4%. Not exactly where I want them to be but it's better than the double digits I was getting.
Thank you guys for your help. I'll post the results of what was found when I find out from the mechanic.
You know what Murphys law says right?.. the one time you don't have time to rip into it and have to take it in... it's gonna be something stupid simple, just watch. Never fails..oh well. As long as you took it to a competent shop they'll find the cause. The "hard" work on FT trouble codes is just doing the diagnosing. I went through something similar just recently, it's turning out that I got some bad gas blocking flow. My LTFT's were double digits recently after picking up some questionable fuel... I'm I the process of cleaning out the system and now my FT's are returning to near normal levels of around 6 and 4%. Not exactly where I want them to be but it's better than the double digits I was getting.
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Originally Posted by NavyVet88
Thank you guys for your help. I'll post the results of what was found when I find out from the mechanic.
Have you gotten the results back yet in order to share with us?
Thank you guys for your help. I'll post the results of what was found when I find out from the mechanic.
Have you gotten the results back yet in order to share with us?
Originally Posted by bdcardinal
Vacuum leak most likely. The hose with the PCV valve that goes into the intake is extremely common to crack on the 3.0L.
X2. The original style elbow gets soft and collapses on the inside of bend and can develop a pretty significant hole, which will cause a lean code for both banks. It's not really noticeable when just glancing around under the hood because of where the hole forms.
The updated hose/tube/PCV valve assembly from Ford has reinforcements molded into the elbow that keep the hose from collapsing.
Vacuum leak most likely. The hose with the PCV valve that goes into the intake is extremely common to crack on the 3.0L.
X2. The original style elbow gets soft and collapses on the inside of bend and can develop a pretty significant hole, which will cause a lean code for both banks. It's not really noticeable when just glancing around under the hood because of where the hole forms.
The updated hose/tube/PCV valve assembly from Ford has reinforcements molded into the elbow that keep the hose from collapsing.
I had the same codes, plus 2 others which are related. So far i've replaced 02 sensor and one of the plug coil. CEL is gone now but once awhile it'll jump into failsafe mode stuck in 3rd gear without CEL. next on the list will be (taking cues from this thread) fuel filter, PCV valve, valve cover gasket.
On a side note, i've also got an oil catch can installed routed from the PCV. would this somehow messes the AF mixture ever so slightly? btw my car doesnt use MAF sensor rather rely on MAP instead for determining air volume
On a side note, i've also got an oil catch can installed routed from the PCV. would this somehow messes the AF mixture ever so slightly? btw my car doesnt use MAF sensor rather rely on MAP instead for determining air volume
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