Oxygen Sensor

[killie77]

Hi

I had an engine management light come on the other day. Had it diagnosed as the O2 Sensor. It appears to be the one at the back of the manifold with the Black plug.Ive had a look on eBay and theirs a Pre Cat and a Post Cat. Any idea which is the one behind the manifold.Dont want to buy the wrong one.

It's 2016 1.2 TSI

Thanks

Ian

[Crasher]

What is the VIN and the fault code?

[killie77]

Vin

TMBFN6NJ2HZ029829

Not sure what the fault code was but I will be able find out later this afternoon for sure.

Thanks

Ian

[nta16]

Be aware that some people just take an error code from a scan tool as the answer, which sometimes it can be but not always, it may be from where the issue is reported rather than the cause of the issue and replacing the reporting sensor can be shooting the messenger.

 

Also be aware German marques particularly, including our dear VW, have always thought it clever to have very complex, intertwined and involved (and interfering) computer programs so the scan tool has to have specific programs for the VW model and year, this is more so with cheap and/or generic code readers and scan tools.

 

Plus the programs have to be up to date or errors or misinformation can be presented, many scan tool owners and mechanics/technicians, engineers, can be too arrogant and/or lazy to be bothered to update scan tool programs.

 

 

[nta16]

ETA; The sensor can also be tested on a scan tool or with a multimeter to confirm if it might be at fault.  Cheap Chinese sensors are a gamble often and even aftermarket parts can be less than perfect match, personally I would go for a good Japanese make, which it maybe from factory.

 

 

[killie77]

Thanks for the replies.

My Stepson who is a very good Mechanic.

Uses an Autel Scanner which he knows his way around. He sent me a Video of the Sensor which has a Black plug on the end.

Due to the location on the Manifold it will have to be given a fair bit of heat to loosen it so that the threads don't strip. He checked with a multimeter on the plug end and he's 99 percent sure the Sensor Lead has gone.

I'll order one this week and hopefully he can fit it this weekend coming.

[Crasher]

Pre cat is 04E 906 262 BH and post cat 04E 906 262 BJ, stick to Bosch or genuine. No heat should be required to release the sensor, it isn't common for the boss thread to Gall but if it does, there isn't much hope of saving the boss and a new one would need welding in. When the sensor releases, it will go with crack and then run smooth, almost finger tight straight away, if it feels tight as it is just moving with an almost rubbery sensation, stop and try and retighten it but it will probaly be too late. After the sensor initailay cracks away, it would not hurt to spray some penetrating oil in the gap.

[killie77]

Many Thanks

I guess my Son always expects the worst thing to happen. Works on Cars Vans and Trucks all day.

[nta16]

Using the correct oxygen sensor socket for that sensor will help and not too much or indirect leverage.  My choice of penetrating/releasing agents are PlusGas or better still for this and other general longer lasting lubrication GT85.  Obviously you don't want to be drip gravity feeding or spraying any stuff on a warm or hot exhaust (or spilling any 3-In-one oil on a cold exhaust, wow the fumes off that next time you start the engine, guess how I know).

 

[killie77]

Glad I'm not the one fitting it. 😭

[Crasher]

@nta16 If you fancy experimenting then try some of this, it is amazing stuff https://www.lubricantsuppliers.com/product/bdx-01-bulldog-bdx

 

@killie77 All mechanics end up feeling that way after about a week in the job, never mind after 42 years!

Edited 20 hours ago by Crasher

[nta16]

To me the most unnerving bit is unclipping or disconnecting any plastic connector and they all seem to vary as to how you do this and don't suit my stubby little sausage fingers and hands and those aged plastic near to heat too add more fear, after that getting at the sensor might be 'fun' but removal and replacement of the sensor is just unscrewing it and screwing it back in (without twisting the wires), easy - that of course is until it isn't. 😆

 

Thing with doing it yourself is that you can allow yourself all the time and patience you have available to do just this job without time and work pressures to rush/bodge it to get on to other stuff.

 

[nta16]

5 minutes ago, Crasher said:

If you fancy experimenting then try some of this, it is amazing stuff https://www.lubricantsuppliers.com/product/bdx-01-bulldog-bdx

Funnily enough I saw this only last week when looking for a link for PlusGas, I'd definitely give it a try as I don't think PlusGas is as good as it used to be but perhaps that's rose-tinted glasses I only went to it when my drip can of Rapideeze finally run out.  I use up most of my lubricants doing free work for neighbours and often give them the can I'm using so get down my stock quicker.  Just recently with one neighbour that I'm doing some regular "gardening" for (with Chinese motor, and carb, mower that he manages to abuse and neglect when I'm not around) I started using the (second and full) can of GT85 I'd left with him and when it ran out I said he could buy two and give one to me but I bought another three cans and took one over to him to have, Sod's Law he'd bought two cans but they'd not arrived.  His, when they turned up, were £12.74 for the two 400ml cans (mine £2.75 each), I've told him countless times not to bother with Amazon, my wife picked mine up at ASDA or somewhere.

 

As I no longer have old over-valued and overpriced cars (called "classics") my needs are reduced but I always believe in letting chemicals do the hard work where you can (and have lost what little muscle I had, but the fat returned) I'll keep an eye out for it because if it saves hassle when farting about on cars it's worth every penny to me, my neighbour who had all the garage tools has now moved away, luckily I never needed the 5' breaker bar, probably best as when he lent me one his longer knuckle-saver spanners to get at something in a tight space I tweak'd up too much and stripped the thread, doh, I would have been mad at myself but I know I'm an idiot and at least I'm cheap to employ (as long as I don't break too much).

 

[Crasher]

@nta16 I found it by accident. I was sitting back with a large vodka in one hand and the latest (at that time) copy of Practical Classics in the other and there was a piece about Powdercoat repair spray so as I am doing a full resto on a 94 S2 I thought it would come in handy for touching up the inevitable chips in all the lovely RAL9005 bits... it is a bit thin to use as a touch up (decant and leave to thicken) and a bit shinny for me.

 

Then out of the blue their rep called me and we got chatting, apart from him being in Belfast and randomly knowing the owner of a Scirocco GTX we have just finished for a chap in Scotland, he got me to order a mixed box of six so I had two more black, two cold galve (excellent stuff) and two DBX. I was a bit sceptical but one of the lads was struggling to get a Golf 2 16v seat to move last week as the mechanism was all rusted up, spayed it on, gave it overnight and bingo.

 

I hope it may come in handy next time I get a PQ35 platform car with the brake pedal sticking down due to the pivot pin rustsing.