Advice on Code P0171
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The code indicates a lean air-fuel mixture. Typically, these codes do not pinpoint what is causing the issue, so further diagnosis is required. In this case it could be one or more of 8-10 different possibilities.
You could start by having all the EGR ports cleaned, as recommended, however, that may not resolve the issue. Next you could replace the O2 sensor and if that doesn’t fix it move on to the next most likely component. Eventually, you may end up replacing 7 or 8 parts that didn’t need replacing before getting to the one that does. This isn’t an efficient or economical approach.
My advice, if you don’t have the tools or knowledge to diagnose the code, is to take it to a dealer and have them do the work. It’s an emissions issue and should be covered under the Federal Emissions Warranty, which at a minimum is 8 years or 100,000 miles in the US.
You could start by having all the EGR ports cleaned, as recommended, however, that may not resolve the issue. Next you could replace the O2 sensor and if that doesn’t fix it move on to the next most likely component. Eventually, you may end up replacing 7 or 8 parts that didn’t need replacing before getting to the one that does. This isn’t an efficient or economical approach.
My advice, if you don’t have the tools or knowledge to diagnose the code, is to take it to a dealer and have them do the work. It’s an emissions issue and should be covered under the Federal Emissions Warranty, which at a minimum is 8 years or 100,000 miles in the US.
MrFixit
Well-Known Member
You asked whether the fuel pump could be related... I wouldn't have thought it was likely, but while googling I found this:
https://sagelawgroupllp.com/acura-honda-fuel-pump-recall-can-you-file-a-lawsuit-in-2024/
This article (well, it is a law group) specifically states that P0171 can be a sign of a pump defect.
Let me postulate something else - Could this code have perhaps been "left over" from a bad pump (before it was replaced) and never cleared? I do agree with @Landshark however that this is emissions related and hence should be covered under warranty. It may be best to let this fall to the dealer. Often a dealer may clear the code and send you on your way just to ascertain whether it is persistent or a one-time hiccup.
Joe17
Member
From the manual;
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- Fuel pump failure
- Fuel injector failure
- Fuel pressure regulator failure
- Fuel line failure
- Fuel supply system failure
- Mass air flow (MAF) sensor range/performance problem
- Manifold absolute pressure (MAP) sensor range/performance problem
- A/F sensor (sensor 1) failure
- Secondary HO2S (sensor 2) failure
- Vacuum hose misinstalled
- Throttle body air leak
- Intake manifold air leak
- EVAP canister purge valve failure
Yep, the codes don’t always provide a specific diagnosis.
Our new Ram truck, had a CEL the day we tried to buy it. They couldn’t resolve the issue so we picked it up the next day at 6pm after waiting an hour and a half for them to resolve another CEL. The back story is that the battery was dead when we tried to take it for a test drive. They jump started it, but I asked if they would replace the battery. They agreed. Then I was told it had to sit for 4 hours to “reprogram” so we decided to go back the next day.
We waited the second day because they had just replaced the stop/start battery, and they were having similar difficulties “programming”. The CEL came on that evening on the way home. I called the dealer the next morning and took it in. The mechanic told me it was a communication error. The CEL came on again that night. I called the dealer, which is an hour away and is not the same dealer where we take the Jeep. I said I was going to have the code read and then schedule a visit with our regular (closer) dealer. The code came up as “Starter Relay ‘C’ stuck On”
Within 15 minutes of the truck going into service at our regular dealer, the service advisor came out and presented a bus bar with a blown fuse. He said the blown fuse prevented the batteries from being charged. I can’t prove it, but I suspect that the fuse was blown before the test drive and the selling dealer just kept throwing parts at the problem rather than trying to figure out what was causing the problem. We haven’t had a CEL since the fuse was replaced.
If there’s a moral to this story it is that the cause of the problem has to be identified and all service departments are not equal.
In total, I spent 11-12 hours over a 5 day period dealing with this issue. The dealership wants a perfect score on the “dealership experience” survey. I spoke with the General Manager and informed him that this has not been a satisfactory experience. He asked what he could do to get a perfect score. I asked for a $2000 set of running boards. He agreed.
Our new Ram truck, had a CEL the day we tried to buy it. They couldn’t resolve the issue so we picked it up the next day at 6pm after waiting an hour and a half for them to resolve another CEL. The back story is that the battery was dead when we tried to take it for a test drive. They jump started it, but I asked if they would replace the battery. They agreed. Then I was told it had to sit for 4 hours to “reprogram” so we decided to go back the next day.
We waited the second day because they had just replaced the stop/start battery, and they were having similar difficulties “programming”. The CEL came on that evening on the way home. I called the dealer the next morning and took it in. The mechanic told me it was a communication error. The CEL came on again that night. I called the dealer, which is an hour away and is not the same dealer where we take the Jeep. I said I was going to have the code read and then schedule a visit with our regular (closer) dealer. The code came up as “Starter Relay ‘C’ stuck On”
Within 15 minutes of the truck going into service at our regular dealer, the service advisor came out and presented a bus bar with a blown fuse. He said the blown fuse prevented the batteries from being charged. I can’t prove it, but I suspect that the fuse was blown before the test drive and the selling dealer just kept throwing parts at the problem rather than trying to figure out what was causing the problem. We haven’t had a CEL since the fuse was replaced.
If there’s a moral to this story it is that the cause of the problem has to be identified and all service departments are not equal.
In total, I spent 11-12 hours over a 5 day period dealing with this issue. The dealership wants a perfect score on the “dealership experience” survey. I spoke with the General Manager and informed him that this has not been a satisfactory experience. He asked what he could do to get a perfect score. I asked for a $2000 set of running boards. He agreed.
Joe17
Member
Step 1, with the P0171, is to clear the code and enter maintenance mode and let it idle for a bit. At least until the cooling fans come on. Then check for a code or pending code again. And then drive it with the engine on to see if the code comes back. It also mentions that is there is a different code along with the P0171 then troubleshoot that code first.
Your dealer probably hasn't written any letters to Stellantis, begging the company to release the Ram 1500 Ramcharger ASAP.
I re-wrote it 3 times, so that much thought.
I'm so lucky my Honda dealer has great mechanics who have been able to provide great service for my Insights (3) and Clarity. It's sad to hear stories about dealers who cannot provide this kind of service--especially when the closest dealer is as far away as yours is.
Perhaps you didn’t completely understand my story. We bought the truck from a dealer that is not the nearest one to us. They had more vehicles in stock and some significant discounts on a few in particular. Their service department, in my opinion, had some difficulty in diagnosing a CEL and resolving the issue. It’s possible that the CEL was different each time, but they didn’t take note of the codes, or at least they weren’t willing to share that information with me. What I know is that our closest dealer, where we’ve taken our Jeep in the past, diagnosed and resolved the issue. They have provided excellent service. I don’t intend to take the vehicle to the selling dealer, but they wanted the opportunity to try to fix it, so I gave them a shot.
You may recall that one of our members has had a less than satisfactory experience with his Honda dealer in Eugene Oregon. So even your beloved Honda brand has flawed service departments. You’re fortunate to have a reliable service department nearby. You could just as easily have a terrible one nearby.