mylona78

Hello.The yellow engine light showed up giving codes P0170 and P0171. Maf is brand new but what i have noticed on torque pro app is tha bank 1 sensor 1 does not give any readings or voltage . Do you believe this is the reason ?

kev95

My torque app also doesnt show first o2 sensor voltage.
Mu p0171 and p0170 problems started because oil in wire harness. Check your camshaft magnet plugs

mylona78

Ok i will have a look does anyone else has an idea ?

mylona78

yes you are right their ar leaking ... a little bit . how to remove oil from harness ? it seems it travelled all the way to ecu because i found some oil there

kev95

Check o2 connectors too. I replaced both cam magnets, added "pigtails", replaced front o2 sensor(rear sensor plug was clean).
For the wire harness, I used contact cleaner spray, alot of it.
After fix, it was good for ~ 400km but then CEL came back with P0170 code. I havent found out what the issue is yet.

mylona78

cheers

kev95

I will give you product numbers for magnets and pigtails so you could stop existing oil leak into wire harness.

2x A271 150 27 33 - "pigtail" wire
2x A271 051 01 77 - Cam magnets
2x A010 997 23 48 - O-rings for cam magnets.
2x A271 051 00 32 - rubber plugs for cam magnets

mylona78

thanks a lot

mylona78

do you know an online shop to buy them >?

kev95

I bought them from local dealer, total was only 205 euros.

mylona78

but my question remains. the wires have oil in them . how do i clean them ?because they go all the way to the ecu and o2 sensors. do i need to replace them or can i clean them ?and if so how can i clean them ?

kev95

You can replace entire engine wire harness and that would be better than what I did but I went harder and alot cheaper way. I cleaned all plugs that had oil in them and after every 3 days I check and if needed clean plugs again. It should get oil out of them eventually.
Somebody here at mbworld removed engine harness, and soaked them in alcohol I think.

Theoretically you can also open ECU and clean it with contact cleaner too, I didnt.

mylona78

Thanks for your assistance

mylona78

hello there. i have changed the complete wire harness cam magnets for 400 euro in cyprus i think i a good price. but there is a problem still i hope you can help me.
strange coincidence i press the brakes suddenly abd the yellow managment icon appeared and codes p0170 and p0171

kev95

Check 12$ PCV hose, maybe you have an air leak?
https://mbworld.org/forums/c-class-w...placement.html

Did you check you O2 sensor plugs for oil? If they have oil in them, they are probably dead too.
Also it wouldn't be bad to clean MAF with MAF cleaner spray(During PCV hose check/repalcement)




PS:
you can read my threads, I had same problem. Maybe it will help you somehow.
https://mbworld.org/forums/clk-class...p0036-cel.html
https://mbworld.org/forums/clk-class...ion-p0170.html
https://mbworld.org/forums/clk-class...170-p0171.html

mylona78

do you know the lication on the engine for the pvc hose ???i will have a look and tell you

kev95

Look at the thread I posted, there are pictures that show how to dismantle everything and excact location of that hose.
https://mbworld.org/forums/c-class-w...placement.html

mylona78

hi thanks for your assistanse so far kev95 . I have check visually the o2 sensors for oil in the plug. i can not see any oil on the plugs . are the o2 faulty ? is there a way i can check them ?if not the 02 then what is the problem if these codes show up ?
p0171
p201c
p201e
p2029

kev95

I think you should check breather hose for cracks and leaks.
https://mbworld.org/forums/c-class-w...placement.html

mylona78

i replaced bretherhose friend as you mentioned above but with no luck. what else to check please

mylona78

I replaced both oxygen sensors and everything ok. It makes me 150 km fuel economy more

TechSuperstar

Follow up question, what was the outcome of reading the O2 sensors? Should we get actual voltage readings when using an ODBII app like Torque or Car Gauge Pro? I'm currently fighting with a P0172 "Bank 1 too rich" code with a rough idle after the engine is at operating temp. Anyway, I was trying to read the sensors but nothing shows up. I had autozone use their scanner which said the sensors were OK but they guy didn't say anything further. I've done a lot of other tests and I think I've narrowed it down to these sensors but I'm trying to be sure. As a side note I did have an oil pan leak that I just fixed and noticed some oil did get into the connectors which I cleaned out. Would the sensors report ok but give bad readings? Would a high end reader be able to get the voltages? What should they be?