Lamda Sensor

[Cherry Red Pocket Rocket]

Just had my car MOT'd and it needs a new Lambda Sensor (which is probably why the engine malfunction light is on and MPG has gone through the floor recently). Can anyone recommend one or is there any information that I need to know about one?

I've found a few on eBay which range between £34-£60. Is this reasonable?

I'm also going to need new break pads on the front and am thinking about doing the rear while I'm at it. I've been quoted a price for about £75 + VAT for the lot. Again, is this reasonable and is it an easy job to do yourself?

Thanks.

[stantheman1]

Hi,

The lambda sensor price looks good but don't forget the Yaris has two of them,(one before the CAT and one after) just be sure to change the right one. BTW how do you know for sure that it's the sensor that's faulty?

[gordonD4D]

had the lambda censors go in a works citroen berlingo van which activated the van into get me home mode . 15 MPH MAX along a dual carrigeway , I drove it for a few miles and gave up and called our own mechanic who decided to tow it home rather than let me drive it

local citroen garage diagnosed the problem as above . the van was also LPG gas converted which is a nightmare and a deathtrap in the winter , the whole fleet of berlingoes had the same problem ( cutting out ) in cold weather leaving you at the wheel with limited brakes and No power steering !!!

[Cherry Red Pocket Rocket]

My Yaris is the Mrk. 1 so I think it only has one at the front of the car (in the engine compartment)?

Do I get an NGK, Bosch or what? Can anyone recommend some good break pads as well?

I know its the sensor thats faulty because the bloke who did my MOT told me that.

[stantheman1]

Hi Rob

All mk1 (petrol)Yaris'sessss have 2 Oxygen sensors one before and one just after the cat, only the pre cat sensor can be viewed from the engine bay but if you care to look underneath you'll be able to see the 2nd (post cat) sensor. The reason I asked how you knew the sensor was faulty is because it is often misdiagnosed (not that I'm suggesting this is the case here) only to find the Mass Air Flow Sensor(MAF) to be the culprit.Btw the original sensors are Bosch!

As for the brake pads have you considered Mr.T? They supply and fit them for £80 inc.VAT.(Fixed price promise)

Hope that helps

PS

Sorry to learn about your job situation!

[Chris81]

You need to find out what the error code is, though no code will tell you exactly which sensor is bad. In any case, my friend had a new cat fitted and the P0420 error code came on a few months after the cat was fitted. Toyota told me it could be due to an aftermarket cat being fitted. Nevertheless the car passed MOT emissions ok so regardlerss of the light being on, the car drives ok.

Is your car on original cat? exhaust? A leak could be causing it. Your mechanic can't say categorically that the sensor is faulty.

Anyway, if you decide to replace the sensors, make sure you get genuine Denso ones for your vehicle, not the generic cheap ones that fit many makes and models.

[Cherry Red Pocket Rocket]

The bloke at the MOT Centre said it failed on the emissions and the reason being the lambda sensor (if my exhaust system was leaking I doubt it'd make the emissions very high, would it?)

Everything on my car is original apart from the back box on the exhaust system which I got replaced last year.

Do I buy Bosch or Denso sensors? Since my car has two, I'm going to buy two and replace them both at the same time. Mr. T wants about £250 for both sensors which is crazy!

Regarding my brake pads, thanks for the suggestion Stan but I've bought some EBC Greenstuff Brake Pads for £50 plus delivery and they're better than OEM Parts so thought I'd give them a try. Have you or anyone used them yourself? Fitting them are a piece of cake so I'll do that myself this weekend too. They're 112 x 45 x 16mm I presume these will fit?

Cheers. The hunt for [now] two lambda sensors continues!

[stantheman1]

If your yaris was built in Japan then chances are it has a Denso sensor as Chris81 points out but the ones built in France use Bosch as far as I'm aware.

Just a word of warning, please do not just jump in and replace both sensors as it is very unlikely both would go together! Get a second opinion, it could be a leak on the exhaust,a faulty maf or even the cat itself but unless you are 100% sure then dont assume!

I came across these if you still need an original sensor: My link

Good Luck

[Cherry Red Pocket Rocket]

As far as I'm aware, it was built in Japan. It has a "made in Japan" sticker on the windshield! Ha ha. I'll go with Denso then if its an original manufacturer part. I'll replace the first one and then go get the emissions checked somewhere and see what they say. How can I find out if its a faulty maf, cat or if there is a leak in the exhaust somewhere?

I really appreciate you taking the time to give me some advice on this one. I went to bed in a stinking mood over it last night and am a little more clearer [and calmer!] this evening!

[Chris81]

Firstly, you need to find out the fault code that your MIL is showing up as that should help shed some light. As I said above, on my friends car, the code was p0420 which means that the post-cat sensor is reading too close a pattern to the pre-cat sensor, in other words, as if the cat isn't doing anything. However, that was after a replacement cat was fitted and that car passed its emissions test so it's unlikely to be the same problem as yours.

The garage you went to should be able to inspect the exhaust closely for leaks/holes. Holes could certainly cause the MIL to be on, and I'm no expert but I suspect it could lead to sensors geting confused and causing the car to run too rich, and so emissions high.

Denso sensors aren't cheap so I agree, if you go down this route, change the pre-cat one first. The post-cat one AFAIK just monitors the gases coming out of the cat and doesn't affect the engine's running, so I can't see how the post cat sensor would cause the emissions to be too high. Of course, it could well be that your cat is knackered.

[Cherry Red Pocket Rocket]

Well, I've tried to start the car this morning and it would start and then shut off a second after. I think its safe to say that something, somewhere has snuffed it! My old man has bought me an NGK pre cat lambda sensor which he'll fit tomorrow so hopefully that'll sort out the problem. If not and it turns out to be the cat, it'll be another expense to rectify! The bloke who MOT'd my car was sure it was the lambda sensor though...

Anyway, does anyone know how to change the brake lining on the drum brakes on the back of a Mrk. 1 Yaris? Is there a how to guide somewhere or anything?

[stantheman1]

"Anyway, does anyone know how to change the brake lining on the drum brakes on the back of a Mrk. 1 Yaris? Is there a how to guide somewhere or anything?"

Haynes manual would be your best bet!

[Cherry Red Pocket Rocket]

I had one but am not sure what I did with the damned thing. I might've sold it and am wishing that I didn't, now!

Anyway, replaced the lambda sensor with an NGK one this afternoon along with the front brake pads and it is running beautifully! Just need to take it to a garage to get the Malfunction Light turned off and the emissions checked to make sure everything is ok. I'm particularly pleased with the EBC Greenstuff Brake Pads and thouroughly recommend them!

Now to change the rear brake lining and hopefully that'll last my Yaris for the rest of its days!

[stantheman1]

Glad you seem to have it sorted. Have you had a look at the rear brake linnings? They may just need servcing i.e. cleaning out and re-lubing (not the friction surfaces I might add!)

PS

I know what you can get your dad for Christmas..... a code reader! (£20- £30 ebay) He'll be happy and you get a free reset whenever required.

[Cherry Red Pocket Rocket]

I've had a look at the rear brake linings and they need replacing as they're quite low! Like the front brake pads, they're the originals and the car is eleven years old now! Got them already and they weren't that expensive. Just need to fit them now which might be tricky! Any idea how much a garage would charge?

Bought the old man a set of ring spanners as thanks :D might look into getting a code reader though ;)

[stantheman1]

My guess would be about 1 hour of labour.

[Cherry Red Pocket Rocket]

Right!

I've changed the sensor and have fitted the new brake pads on the front (which are amazing, well worth the money!) just need to get the rear drums done while I'm at it. Will probably do it in the new year or get a garage to do them for me.

UNFORTUNATELY, my Yaris stalls intermittently!

When I start up the car, often it'll start fine but sometimes it'll start and then immediately stall. It was fine all of last week but this morning I started it and it stalled five times! Is there any reason as to why?

[Cherry Red Pocket Rocket]

Help, anyone?