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Troubleshooting Lean Conditions

ldmckiny

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Location
Fort Worth, TX
Genesis Model Type
1G Genesis Sedan (2009-2014)
Picked up a 2009 3.8 sedan for a really good price. Check engine light diag states lean conditions in all bank 2 cylinders.
so far have put in new pump, new plugs, and new coils. Have sprayed the MAS and cleaned the throttle body. Still have the same issue.
I assume the plugs were all changed on the same date but here is a picture of them showing the difference in how they are burning. Bank 2 on the left. Bank 1 on the right.
still throwing codes.
any ideas on additional steps would be really appreciated!
 
What is the error code? I had a an air leak in the manifold intake and this caused a lean condition error. A check valve had mysteriously disappeared, so the intake was taking in outside air.
 
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Code P0174 and P0300. (Forgot to attach the picture. Here is what the plugs look like)
 

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Not to beat a “slow” horse but how can the codes all come up for lean conditions on just one bank and the obvious results (The plugs) be lean on just one side.
This is a real head scratcher for me.
Fuel injectors possibly??
 
Fuel rail issues?
Clogged rail or maybe a pinched fuel line?
 
Lean conditions are caused by...

1) not enough fuel.
a) injectors b) pump c) filter

2) too much air.
a) manifold leak b) O2 sensor c) MAF/MAP d) throttle body e) ECU
 
Picked up a 2009 3.8 sedan for a really good price. Check engine light diag states lean conditions in all bank 2 cylinders.
so far have put in new pump, new plugs, and new coils. Have sprayed the MAS and cleaned the throttle body. Still have the same issue.
I assume the plugs were all changed on the same date but here is a picture of them showing the difference in how they are burning. Bank 2 on the left. Bank 1 on the right.
still throwing codes.
any ideas on additional steps would be really appreciated!
Probably too simple of a fix, but here is another Hyundai car that has the P0174 code and it turned out to be bad intake tube with cracks that was letting in too much air for the fuel system to account for hence the lean condition of the engine.

The P0300 could from a fouled/faulty spark plug or bad coil pack that is misfiring or even from a intake leak as well. Issue was a bad coil pack in the video.
 
For anyone wondering what the outcome of this condition was....

After I had replaced the plugs and coils, replaced the fuel pump housing and filter, checked for vacuum leaks, removed and inspected the plenum, cleaned the MAS and the throttle body then ran a third diagnostic check at Auto Zone the summary of which now pointed to a leak in the intake manifold, ordered new gaskets and removed the plenum again to find I had received the wrong size gaskets.... inspected carefully and decided the current ones were ok, so.....nothing changed. All Auto Zone codes pointing to lean conditions on bank 2....still

At this point I decided to quit trusting Auto Zone’s $20.00 tester and took it to my mechanic for a thorough diagnostic and he found a faulty O2 sensor.
That was it!! $189.00 out the door for the diag, sensor, and labor.
Now this really inexpensive ($350.00 + $400.00 parts and labor) purrs like a “lion”.

I know I needed new plugs and cleaning the MAS and TB could only be good, but my whole point in this long winded summary is that I could have saved a lot of time and a little money by staying away from Auto Zone and the myriad of possible causes their little reader spits out.
I’m especially doubtful of the need for fuel pump and coils.....

I appreciate all the input and time to respond as I was working through this. I love being able to participate in this forum and love having this really cool car that runs and rides like new.
 
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