Please help a newbie! C02 sensors query

[Stew]

Hi all my engine management light came on last week (orange one) and the fault code was read and temporarily cleared yesterday:

Car is a 2008 197 cup:

I have ordered and received part number:
8200830903.
But my mechanic reckons the dealer i got the car from knew the fault and due to the faff involved in replacing the sensor couldnt be assed doing it:
He also thinks ive got the correct part which i believe is the "2nd sensor" of the two that these cars have, yet he persistently told me it was the "first sensor" that was at fault and set about changing it only to admit defeat due to in accessibility. I tried to explain that i had bought the "2nd sensor" and not the "first" one and that they were different.

Oddly though renault parts direct seem to have both items at the same price and they look identical? (£135?)

I think from reading up on this i need

Part number: 7700107433? (Renault number)

"2nd sensor" which i have:


And this one is the "first sensor"?? That i need?



Many thanks indeed for any help, i know this question is probably as old as the hills,

Cheers, Stew

 

[RSRowe]

Did he tell you what the fault code was?

 

[Stew]

Hi sorry i have just seen your reply:

It was something along the lines of


174:
"downstream oxygen sensor heating power circuit non compliance with pollution standards current"
P2075 undocumented code

Read on a snap on sollus ultra machine

Any help v much appreciated,

Thanks Stew

 

[RSRowe]

It would be good to get some clarification

P0174 could suggest an exhaust leak as opposed to the lambda being at fault.

The description about the heating element would suggest lambda is goosed

P2075 could mean the accoustic valve on the intake is disconnect.

Have you had any work done recently?

 

[Stew]

It would be good to get some clarification

P0174 could suggest an exhaust leak as opposed to the lambda being at fault.

The description about the heating element would suggest lambda is goosed

P2075 could mean the accoustic valve on the intake is disconnect.

Have you had any work done recently?

Hi its got a really embarrassing induction cone fitted, but it sounds awesome!

I bet something is disconnected yes!

Many thanks, stew

Are both lambda sensors the same?

 

[RSRowe]

It's worth checking to see if the acoustic valve is plugged in then. Tuck it out the way but plugged in if you're leaving the cone on.

And I'm not entirely sure. I would think they'd be different to be honest.

 

[Stew]

Thank you for your help mate, can you tell me where the accoustic valve is please? (Or what it looks like?) There is a thin black tube which is semi tucked away around the scuttle area/battery, my mechanic actually said "what's this?" And blew down it, then he said he thought it was something which belonged to the orginal airbox like a breather pipe?

Funny how both lambda sensors from renault are £135 yet the "1st " one is available for a fraction of the cost elsewhere and is a bosch item too so its not exactly inferior quality. My mechanic confused me somewhat saying he was going to replace the "1st " sensor yet i clearly only had the "2nd" one with me! Hence my doubts, yet he insisted i had the correct one! What a joke!

 

[Foxspeed]

there are 2 sensors...the first is the important one as thats the one that sets the fuelling..the second one monitors the first ie for emissions failures (obd2 regs) and is usually the one to put the eml on when it detects issues...if you access the onboard diagnostics you can if you have the equipment look at the voltage swing of the 1st sensor as they slow down when worn or faulty and hence provide poor fuelling and running faults

 

[Stew]

Hi, thank you all for the help,

Foxspeed: thank you, we did monitor the fluctuations on the obd reader yes, it was
"Allover the place" (1st sensor)

My mechanic said the of the first sensor: "no wonder they didnt bother changing it, its extremely difficult to access!" (Or words to that effect!)

I tried to explain i didnt have the first one! But he said "youve got the right one!"
I realised i wasnt getting through to him at this point!

I didn't want him to break the sensor whilst attempting to remove it, then realise i didnt have the right one as i was at his house and didnt fancy getting stranded.
I think i will order the first sensor now and get them both changed to be on the safe side.

Ive looked at the accoustic valve: the airbox pipe is obviously not there now as its got an open cone fitted, and i did notice that the breather pipe is still connected from the throttle body around the back of the battery to the accoustic valve:

I have read that disconnecting this breather is the trick? Rather than simply removing the hard plastic pipe to the valve from the airbox and still having the breather plumbed in as mine currently has.
Ill get there in the end im sure !
Many thanks for all the help,

Stew