Running rich banks 1 and 2

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This is on my Land Rover LR3. Got gas the other day and drove it home, parked it. When I started it, the CEL was on and it was bucking a bit, but normalized pretty quick. I stopped by the guy I use and he very kindly scanned the codes for me and looked at the fuel trim data. It wasn't running rich at that time.

Here are the codes:
P0172 system too rich bank 1
P0175 system too rich bank 2
P0480- 14 fan 1 control circuit (historic code)

He mentioned it could be the MAF sensor. It's a new Denso one I got from amazon for $50 last summer. I bring that up because I'm wondering if it I got a counterfeit one?

Any ideas about the codes? Thanks much!
 
I agree with your analysis... new inexpensive sensor off of Amazon followed less than 6 months later by an issue that sensor can cause...
 
So , it throws a code when cold ?

First thing I would do is physically examine the Amazon sensor . Make sure it is making good electrical conection ( un-plug & re-plug it ) . Look for physical damage .

Best of luck to you ! :)
 
It could be the MAF but repair the P480 first as it is a known issue. The P480 can be a few things inc the VSS sensor, this can effect other components. Unplugging the MAF will send the ECM to default parameters, monitor the fuel trim to see how it reacts in closed loop.
How does it run cold?
 
It's fine when cold. It had been parked for maybe an hour...so it was still warm I'd say. It's had a trend of sometimes doing this after getting gas.

So start with the 480? I was just doing more research on that. The fan is mechanical with an electronically controlled clutch. Is it possible that could be a code left over from when it was like -15F? The fan roared pretty good for a bit until it warmed up. Thought it was normal.
 
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I just had similar faults on a Volvo, which may actually be similar to the LR. Clean the throttle body really well, and clear all faults and adaptations. Leave the key forward for about 2-3 minutes after and the car should do a learn on its own.
 
I was just googling that and it seems like the TB is common culprit. I cleaned a year or two ago but it might be due again.
 
Originally Posted By: HoosierJeeper
It's fine when cold. It had been parked for maybe an hour...so it was still warm I'd say. It's had a trend of sometimes doing this after getting gas.

So start with the 480? I was just doing more research on that. The fan is mechanical with an electronically controlled clutch. Is it possible that could be a code left over from when it was like -15F? The fan roared pretty good for a bit until it warmed up. Thought it was normal.


Cold like that can cause all sorts of little electrical gremlins to pop up, clear the codes and get a fresh start on this.
How long and how many tanks of gas has this been going on?
 
You may be able to just leave the key forward and let it adapt to the dirty throttle, but it may not be 100%
Also I had another one come back a few hundred miles later with mass maf correlation, mass air flow fixed it for 6 months now, so may have 2 issues, but Id imagine the throttle is a better place to start.
 
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It happens maybe 5-10 times a year, for the past 3 or 4 years. The first time it happened I want to say the codes were similar (it actually had lean ones too) and I was in the middle of nowhere, so a reman Autozone MAF had to do. Worked fine for a year, then same thing. Got another Autozone MAF and it worked fine. Then last summer it was acting up again so I got the Denso thinking that'd fix it. There seems to be loose correlation between getting gas and it bucking, but 95% of fillups it's fine and not every bucking episode is after getting gas.
 
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Just thinking out loud to myself. I wonder if it might have a saturated carbon canister when you fill it. Once the purge valve opens in closed loop it would get a large amount of fuel for a short time.
I don't think there is any code for the can itself if saturated.
 
About a year ago it got codes for the purge valve sticking open and something about the carbon canister but I can't recall the specifics. Replaced the purge valve assembly then. The other code it gets sometimes is one for the leak detection pump not working. One other interesting thing that happened a few months ago is after getting gas, I drove it home (drove fine and normally), and gas was pouring out of some hose under it. It stopped and hasn't done it since, chalked it up to an overzealous pump.
 
IMO this seems like right track. Time to do some diagnosing on that system. Do you top off the tank after the pump automatically shuts off? If so stop.
 
Could be the MAF indeed. Once had a bad drivability problem on a supercharged Jaguar with a Denso MAF for a while until it finally set a code for banks lean (opposite of your prob). Eventually decided to go over the MAF with great detail and found a speck of contamination on the tiny hot wire which required a q-tip to gently remove. Problem solved. At least check it with a bright light for debris or contamination on the sensor
 
Originally Posted By: PeterPolyol
Could be the MAF indeed. Once had a bad drivability problem on a supercharged Jaguar with a Denso MAF for a while until it finally set a code for banks lean (opposite of your prob). Eventually decided to go over the MAF with great detail and found a speck of contamination on the tiny hot wire which required a q-tip to gently remove. Problem solved. At least check it with a bright light for debris or contamination on the sensor

Did getting gas ever effect it?
 
Yes that is correct. Seeing as this is so infrequent I don't have much faith in a bad NAF but its possible so I hope you check this out thoroughly.
On the other hand seeing has this had had issues for some time apparently related to this part and it cost less than an hours labor that it would take to diagnose it I would probably take a chance on it, make sure to check every hose, cable and connection in the system.
 
Found the charcoal canister separately....
https://www.genuinenewparts.com/oem-part...vgaAnlcEALw_wcB

Pardon my ignorance, but what's NAF?

I guess what I'm thinking now is the charcoal canister makes sense but could that be this intermittent? I can't find anyone on the LR forums that has had to replace the charcoal canister...a few the leak detection pump, for the P2402/2406 codes.
When I google the codes I got this go around, it seems like MAF and TB are the common culprits on the LR forums. I can think of a few instances were it's ran rough without getting gas recently too.

Just typing out loud. Thanks for the help so far everyone!
 
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