Code P0161?
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From: Vancouver, B.C., CANADA
2006 E55 AMG/1996 C36 AMG/1999 C43/55 AMG/2021 Toyota Tundra Crew Max TRD Sport Premium
Code P0161?
Finally my CEL came on as I was experiencing misfiring. Code P0161 showed up on a scan. I know that it refers to the left side post cat 02 sensor but I want to make certain that this will cure the misfiring issue that I'm experiencing. Any help is greatly appreciated.
Cheers
Cheers
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From: Sydney, Australia
190D 2.5 (x2), 190E 2.6, W202 C240,W202 C43 (C55), W210 E55, W212 E250CDI
That wont have any effect on engine running in ANY way.
The downstream o2 sensor is there solely to monitor cat function. If it doesn't bring an engine light on and you don't have emissions testing for rego then don't worry about it.
With your scanner can you look at engine adaptation values or smooth engine running?
The downstream o2 sensor is there solely to monitor cat function. If it doesn't bring an engine light on and you don't have emissions testing for rego then don't worry about it.
With your scanner can you look at engine adaptation values or smooth engine running?
Thread Starter
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Joined: Mar 2008
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From: Vancouver, B.C., CANADA
2006 E55 AMG/1996 C36 AMG/1999 C43/55 AMG/2021 Toyota Tundra Crew Max TRD Sport Premium
Thanks guys! I was encountering misfiring on cylinders 5,6 & 7 prior to replacing valve cover gaskets and breather seals as oil was seeping into the plug cavities. Although not nearly as bad as it was, it still feels like something is causing hesitation and holding her back at full throttle. The cel finally came back on and those are the codes that popped up during a scan. Perhaps it is a bad plug that is causing the misfire. I cleaned the maf sensor a few months back as a scan recognized a hot film build up in the maf. Perhaps, it is on its way out! Would a faulty maf not show up on a scan? I also cleaned the fuel system, thinking that that an injector was clogged. This is very frustrating, to say the least! Coils are new and wires appear to be good. I'm running NGK iridium ix plugs and perhaps they were not a great choice.
Thread Starter
Super Member
Joined: Mar 2008
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From: Vancouver, B.C., CANADA
2006 E55 AMG/1996 C36 AMG/1999 C43/55 AMG/2021 Toyota Tundra Crew Max TRD Sport Premium
That wont have any effect on engine running in ANY way.
The downstream o2 sensor is there solely to monitor cat function. If it doesn't bring an engine light on and you don't have emissions testing for rego then don't worry about it.
With your scanner can you look at engine adaptation values or smooth engine running?
The downstream o2 sensor is there solely to monitor cat function. If it doesn't bring an engine light on and you don't have emissions testing for rego then don't worry about it.
With your scanner can you look at engine adaptation values or smooth engine running?
Cheers
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98 C43, 15 Alfa 4C LE, 18 Tesla Model 3 DM Perf, 08 Duc S1000, 02 Duc 998, 98 Duc 748, 01 Miata
Thanks guys! I was encountering misfiring on cylinders 5,6 & 7 prior to replacing valve cover gaskets and breather seals as oil was seeping into the plug cavities. Although not nearly as bad as it was, it still feels like something is causing hesitation and holding her back at full throttle. The cel finally came back on and those are the codes that popped up during a scan. Perhaps it is a bad plug that is causing the misfire. I cleaned the maf sensor a few months back as a scan recognized a hot film build up in the maf. Perhaps, it is on its way out! Would a faulty maf not show up on a scan? I also cleaned the fuel system, thinking that that an injector was clogged. This is very frustrating, to say the least! Coils are new and wires appear to be good. I'm running NGK iridium ix plugs and perhaps they were not a great choice.
Thread Starter
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Joined: Mar 2008
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From: Vancouver, B.C., CANADA
2006 E55 AMG/1996 C36 AMG/1999 C43/55 AMG/2021 Toyota Tundra Crew Max TRD Sport Premium
When my MAF died, I could feel the drop in performance long before it threw a code. Unfortunately, it is tough to tell if that is the cause until it does throw a code unless you don't mind throwing parts at it. There may be a diagnostic that can be done on the sensor that I'm not aware of.
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C43 5.4, ML320CDI, Fords
Often times a bad maf will show up in misfires before it shows up setting faults for the fuel mixture adaptation. They will run so badly in the upper rpm range that it will then misfire.
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From: A.D., U.A.E
2000 (W202 C200) & 2000 (W202 C55)
+1,
MAF is an Enemy to all air system, either ECU doesn't like it..
,
the MAF film is soo sensitive and not gives clear codes while the car is running...
ZAYED,,
MAF is an Enemy to all air system, either ECU doesn't like it..
, the MAF film is soo sensitive and not gives clear codes while the car is running...
ZAYED,,
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From: MN, USA
C43 5.4, ML320CDI, Fords
it may not give off a code, but it is still easily diagnosed if you have the test equipment to look at the part load fuel mixture adaptations... they will be getting towards 1.30 both banks.
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I don't remember the exact code, but I think it will give you two codes which will be something to the effect of Lean Fuel Mixture Bank 1 and Lean Fuel Mixture Bank 2. When you see the same code for both banks, that is what indicated the MAF failure on mine.
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From: Vancouver, B.C., CANADA
2006 E55 AMG/1996 C36 AMG/1999 C43/55 AMG/2021 Toyota Tundra Crew Max TRD Sport Premium
Problem eliminated! Added 1 bottle of Chevron Techron fuel system cleaner to the gas tank when almost empty. Added no more than 15 gallons of fuel and after a few days it started to run better. Added a second bottle when fuel was low and a few days later the cel went out and runs like a charm now with no hesitation or misfiring. It has been three weeks now and still running strong. Thanks to everyone for their input, help and advice.
Cheers
Cheers
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Good job and also a sign that perhaps the injection system needed come cleaning. Something which could be done from time to time (1-2x a year)
