running rich help
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2019 c300
running rich help
Ok yesterday I get a check engine. So this morning I plug in the reader and get back PO172, Running Rich bank 1.
The car is at about 49000, C230K 04. About 500 miles back I noticed the cam sensor connectors were slightly oily so I replaced the sensors and have the extended harness in place. I didnt check the MAF sensor at the time.
Can anyone provide some insight as to what I should check / replace, O2 sensor? plugs?
My first thought was crap I have the change the engine harness from the oil seapage, but hopefully not
.
Thanks
The car is at about 49000, C230K 04. About 500 miles back I noticed the cam sensor connectors were slightly oily so I replaced the sensors and have the extended harness in place. I didnt check the MAF sensor at the time.
Can anyone provide some insight as to what I should check / replace, O2 sensor? plugs?
My first thought was crap I have the change the engine harness from the oil seapage, but hopefully not
.Thanks
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2019 c300
Ok thanks will give it a go. Although I only use OEM air filters and its a new filter since 46000 miles.
After cleaning the MAF do you have clear the CEL or will it just turn off on its own?
After cleaning the MAF do you have clear the CEL or will it just turn off on its own?
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Cancel the code. Unplug the MAF and run on a default map & see what happens. If no code comes back you know it's the MAF.
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03 g35 coupe...........02 c32 Sold
i would check the primary 02 sensor if that doesn't work. THe 02 sensor could be bad..putting the car in limp mode. The car's probably running rich to prevent detonation.
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late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
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2019 c300
I have seen some postings regarding replacing the o2 sensors but none have diagrams or picts. Can you tell me where the location or o2 sensor 1 is? Is it on the manifold or underbody?
Should I just replace it or what to check for?
Right now the car is not in limp mode, rough idle or any symptoms if not for the light it runs the same as when there was no CEL.
Should I just replace it or what to check for?
Right now the car is not in limp mode, rough idle or any symptoms if not for the light it runs the same as when there was no CEL.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
I have seen some postings regarding replacing the o2 sensors but none have diagrams or picts. Can you tell me where the location or o2 sensor 1 is? Is it on the manifold or underbody?
Should I just replace it or what to check for?
Right now the car is not in limp mode, rough idle or any symptoms if not for the light it runs the same as when there was no CEL.
Should I just replace it or what to check for?
Right now the car is not in limp mode, rough idle or any symptoms if not for the light it runs the same as when there was no CEL.
https://mbworld.org/forums/c-class-w203/206488-diy-m271-o2-sensor-replacement.html
Will try & find some pics - Do MAF check first - it's easy
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MBWorld Fanatic!
Joined: Dec 2007
Posts: 5,034
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From: Corona, CA
03 g35 coupe...........02 c32 Sold
I have seen some postings regarding replacing the o2 sensors but none have diagrams or picts. Can you tell me where the location or o2 sensor 1 is? Is it on the manifold or underbody?
Should I just replace it or what to check for?
Right now the car is not in limp mode, rough idle or any symptoms if not for the light it runs the same as when there was no CEL.
Should I just replace it or what to check for?
Right now the car is not in limp mode, rough idle or any symptoms if not for the light it runs the same as when there was no CEL.
Here's a pic of the sensors from install university
http://www.installuniversity.com/mb/...ans_oring.html
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Read this tread as well. It covers all your potential issues with a good explanation of where the sensors are
https://mbworld.org/forums/c-class-w...ght=sensors+02
https://mbworld.org/forums/c-class-w...ght=sensors+02
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2019 c300
Awesome. That pic helps a lot.
Well last night before driving home I cleared the code, and unplugged the MAF and went 20 miles, no CEL. Came back into work today 20 miles no CEL.
So i am going to try plugging it back in heading home and see what happens today.
Well last night before driving home I cleared the code, and unplugged the MAF and went 20 miles, no CEL. Came back into work today 20 miles no CEL.
So i am going to try plugging it back in heading home and see what happens today.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Note that Mikes picture is of a V6, gives you an idea but not quite the same.
Last edited by Glyn M Ruck; Dec 6, 2008 at 12:28 PM.
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W203
Ok yesterday I get a check engine. So this morning I plug in the reader and get back PO172, Running Rich bank 1.
The car is at about 49000, C230K 04. About 500 miles back I noticed the cam sensor connectors were slightly oily so I replaced the sensors and have the extended harness in place. I didnt check the MAF sensor at the time.
Can anyone provide some insight as to what I should check / replace, O2 sensor? plugs?
My first thought was crap I have the change the engine harness from the oil seapage, but hopefully not.
Thanks
The car is at about 49000, C230K 04. About 500 miles back I noticed the cam sensor connectors were slightly oily so I replaced the sensors and have the extended harness in place. I didnt check the MAF sensor at the time.
Can anyone provide some insight as to what I should check / replace, O2 sensor? plugs?
My first thought was crap I have the change the engine harness from the oil seapage, but hopefully not
.Thanks
Unplug the O2 sensors under the car (by the oil drain plug) and spray them several times with electrical contact cleaner.
You are running rich cause the O2 sensor connectors are full of oil, the O2 sensors work by outputting a voltage level, the oil changes the resistance of the connector and affects this voltage level significantly.
The MAF connector is probably full of oil too. Clean EVERY connector on the engine harness. It'll cost you a day of time and $6 of contact cleaner, yet you'll save $350.
Oh, and clean it again months later, cause the engine harness will continue to leak the oil out of it for awhile, yet with the harness extension it'll be minuscule.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Did you clean the engine harness?
Unplug the O2 sensors under the car (by the oil drain plug) and spray them several times with electrical contact cleaner.
You are running rich cause the O2 sensor connectors are full of oil, the O2 sensors work by outputting a voltage level, the oil changes the resistance of the connector and affects this voltage level significantly.
The MAF connector is probably full of oil too. Clean EVERY connector on the engine harness. It'll cost you a day of time and $6 of contact cleaner, yet you'll save $350.
Oh, and clean it again months later, cause the engine harness will continue to leak the oil out of it for awhile, yet with the harness extension it'll be minuscule.
Unplug the O2 sensors under the car (by the oil drain plug) and spray them several times with electrical contact cleaner.
You are running rich cause the O2 sensor connectors are full of oil, the O2 sensors work by outputting a voltage level, the oil changes the resistance of the connector and affects this voltage level significantly.
The MAF connector is probably full of oil too. Clean EVERY connector on the engine harness. It'll cost you a day of time and $6 of contact cleaner, yet you'll save $350.
Oh, and clean it again months later, cause the engine harness will continue to leak the oil out of it for awhile, yet with the harness extension it'll be minuscule.
1 thing at a time. We had a similar problem with another members car the other day and everyone was shouting oil & it ended up being the fuel pump seizing on cold mornings.
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2019 c300
Ok here is the update, I drove to and from work and couple places in between yesterday resulting in about 50 miles with the MAF connected and no CEL.
When I disconnected it and reconnected the MAF there was no oil on the connector. I even took a cotton swap and shoved swabbed it around and no oil. So thats a good sign.
Last time I changed the oil via drain plug I saw some wires right next the plug. But after I was done the thing was drenched in oil so I cleaned it, that was about 1k miles ago. If oil is in the wires would it show by now?
I am still crossing my fingers hoping I dont have to replace the engine harness from oil contamination.
But so far dont know why the CEL popped up.
When I disconnected it and reconnected the MAF there was no oil on the connector. I even took a cotton swap and shoved swabbed it around and no oil. So thats a good sign.
Last time I changed the oil via drain plug I saw some wires right next the plug. But after I was done the thing was drenched in oil so I cleaned it, that was about 1k miles ago. If oil is in the wires would it show by now?
I am still crossing my fingers hoping I dont have to replace the engine harness from oil contamination.
But so far dont know why the CEL popped up.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
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2019 c300
Well CEL came back, same code.
Car is not running rough or limp mode.
So my next step is to clean the MAF and check out the O2's sensor.
Whats the size of wrench to take out the O2 sensors to check for oil or replacement? Or am I suppose to check the plastic part of the connector?
Car is not running rough or limp mode.
So my next step is to clean the MAF and check out the O2's sensor.
Whats the size of wrench to take out the O2 sensors to check for oil or replacement? Or am I suppose to check the plastic part of the connector?
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
I don't know the wrench size. All you need to do is check the plugs & plastic part for oil to see that it is not changing the output value from the sensors & clean with contact cleaner. No need to remove the O2 sensors
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W203
Clean the O2 sensors. Since the cam sensors were leaking, most of the oil leaks down the harness and out the O2 sensor connectors. Give them a GOOD cleaning, I sprayed mine with electrical contact cleaner more than 5 times, and still watched oil pour out.
This might get you back to within tolerances, yet your O2 sensors are most likely done, oil ruins the sending unit.
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2019 c300
Well checked out the sensor plugs and both were dry, not a drop or sign of oil.
Cleaned the maf a bit. Light is still on, should I wait to see if it goes off on its own or should I clear it and see if comes back?
Cleaned the maf a bit. Light is still on, should I wait to see if it goes off on its own or should I clear it and see if comes back?
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Clear it & see what then shows up after a few days use. Good news that the sensors were dry.
