Technical O2 lambda sensor replacing

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Technical O2 lambda sensor replacing

Theleman

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Hi All

My Panda 2010, 1.0L failed MOT due to the Engine Management Light. I am thinking of replacing the old sensors by myself. Any good videos for this? What tools would I need for this job?

Thanks
 
I couldn't find a Good video. I am yet to find one that not stuck


I heat around the sensor to dull red with a plumbers torch


As soon as it moves the tiniest bit I spray some oil on it


Not sure about access as I had the CAT off when I took mine out


Video is a bit rubbish but you get the idea


22mm ring fits better than 7/8"

https://www.youtube.com/watch?v=qSW6qVempkU
 
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Thank you for your advice, and the links. Great stuff.

I should have replaced it last year, but left it as the car had been hardly driven especially during the covid19 lockdown. Now it comes the MOT time, it needs to be done. We forgot even the EML is a MOT fail item, :(

I think the access to the sensors in Panda is quite tight and tricky, especially the bottom one. But from the video, I got rough idea, and know what tools I would need for the job.

Thanks
 
Do you have to take off the Gaskets just underneath the Air Filter Casing to access the sensors? My FIAT is Panda 2010 Eco 1.0L hatchback.
Also do you have to jack up the front of the car to reach the bottom O2 sensor?

I just opened the bonnet and looked at it, and the main problem seems the access room to work on the sensors.
 
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Only done it with the CAT off


I would expect the bottom to be fairly easy from underneath. Ramp should be enough


Tops on the right hand side. I would expect you will have to at least remove the heatshield.


If you have the car High enough. You can remove the four nuts that hold the manifold on and drop the exhaust to the ground. You can leave the rear exhaust mount on. You will need another gasket though. Even this isn't straight forward as you need exactly the right length extension which luckily i had. There's not much room to the radiator.
 
I have to ask


Are you sure the sensors are faulty. I have only seen the heating element fail and thats been due to the wiring causing an engine light.
 
I have to ask


Are you sure the sensors are faulty. I have only seen the heating element fail and thats been due to the wiring causing an engine light.

The sensors are the factory original and they are about 10+ years old. The car gets EML light, and codes indicated the O2 sensors.

The car had no EML at all until it was put in to the local garage for replacing the clutches. Once the work had been done by the garage, the EML came on next day.

We phoned them up and asked about it, and the garage man told us, "It could be 101 things." :(
I was meaning to sort it out last year, but the car was driving fine, so forgot about it. Then the COVID lock down hit us, and the car sat most of this year on the driveway.
 
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If the code says something like O2sensors illogical value or out of range, changing them (the aftercat hardly ever gives a problem as long as the precat sensor works), might be like shooting the messenger. It might indicate a leak in inletmanifold or exhaust before the O2sensor.

gr J
 
I just replaced the top one. But the bottom needed the car on the ramp or jacked up. When I tried jack it up, the jack wouldn't fit due to slightly higher than the car body jack up point.

I now have to bring out the ramps. The bottom one is a nightmare job. I tried crawl under the car, but the space is just too low, no room. I tried to put the rachet from the top of the bonnet and also from the ground either way no room to turn the rachet.

After replacing the top one, I did computer check for the code, and got P0135, sensor 1 Bank 1. So, must it be the bottom sensor?
 
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Just replaced the bottom sensor as well. It was one of the most challenging tasks in my DIY history.

The sensor sockets were useless, they just kept coming off from the hexa of the old sensor. It wouldn't even bite tightly either. What a waste of money it was. A set of Sensor sockets for - I think I paid about £25 - £30 something like that last year from Amazon. :(

I had to get the good old spanner 22mm, and 2kg SilverLine hammer (a fiver from Amazon, I think it was). Once the car was on the ramp, I was able to put on the spanner and hammer it off, and it moved only tiny bit with a heavy blow of about 20-30 times. I kept hammering on for 5 - 10 minutes, and it came off.

I put on both new sensors now, and cleared the code. And when I switched the car off, and waited for few minutes, and started the car again, and the EML didn't come on.

So it looks like a good sign, but this happened before, when I was playing around with the computer keep deleting the code. It didn't come on all day, and then it came back on the next day.

I must see it tomorrow, if it really cleared the EML, or is it kidding on, and return with vengeance, then indicating maybe something else could be at fault? But it would be still good, then because we are narrowing down the problem.

But seeing the old sensors, they looked like from hundreds years ago, all covered with the soot and rust. It would have been weird if they worked from the state of the sensor tips.
 
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Both sensors are the same if you have only one error its worth swapping them over as they are identical. Bit late now as they are already changed


If you have a multi meter check the resistance between the two White wires if the element gone it will be open circuit. Worth checking now as if the old sensors aren't faulty they can be kept as spares


If you haven't got a multi meter put battery voltage across the two White wire and feel if it will warm up


You don't have to touch them to change the clutch. However the wires are very very close. I don't believe in coincidences. Its got to be at least a 95% chance that the two are connected.
 
The 2x old sensors are in my work room now, and I will check them out with my multimeter tomorrow sometime.

If EML returns, then I will check the voltage from the connecting clip of the battery side. If not OK, I will check the fuses of the sensors in the fuse box. If ok, then I will check the resistance of the white wires on the sensor's clip end.

Yes, I feel you are right. The car EML appeared just the day we got the car back from the garage after replacement of the clutch. Never before that moment, for 9 years.

The old bottom sensor was frozen tight, and it was not taking any rachet, spanner or any tools under the Sun. Only way to take it out was the 22mm spanner and heavy hammer, and banging on the spanner locked into the sensor for 10 minutes. At one point, I thought it was not ever gonna come out, and was going to call it a game.
 
I would like to mention a little about spanners and their fit.

Something I use a lot like is a 14mm combination spannerI have acquired a few over the years

For 90% of the time it makes no difference which I use

However on very tight bolts where a hammer or extension bar is required the tighter the fit the better.

The 14mm spanners I own I have measured. There is a sight difference. Te cheaper ones a few thousands of an inch bigger. Doesn't sound a lot but relates to a few degrees extra wobble at the end of the handle.


I have an extra long handled laser 14mm which is the best fitting one I own. No doubt snapon and the like would be the same.


As another side note I have never had a Halfords advance range fail on me with considerable abuse and have a lifetime warranty

Moving back to the sensor its 7/8"

Which is 22.225mm

By using a 22mm is a much tighter fit which is why it doesn't round of even though they are quite soft compared to a bolt

When I require a new socket, hex, spanner that I don't have I buy a decent brand.

You quickly build up a quality set of useful sizes instead of buying complete sets where half are never used.


From personal experience I can recommend Halfords Advance and Laser and wouldn't recommend Aldi normal combination spanners. I don't own but their stubby "look" better made ??? A set of stubby combos is the one "set" I carry mines 10-18 but would be nice if it had a 7 and 8 also


Using the correct tool can turn a difficult job into an easier one or vice a versa
 
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Great post koalar. I was going to mention on the tools too. When I was taking out the heat gasket, there were 4 bolts on it. 3x of them were 10mm, and my 10mm wrench worked fine taking them out. But one of them was 9.5mm. That meant, the 10mm was too big, and 9mm was too small wouldn't fit.

I was glad that I had a Craftsman tool set, I got from Costco a few year ago. It had all these American size sockets in the set. I cannae recall which one it was, and it had one that fitted to the 9.5mm, and took it out no bother.

But yeah, having the tools fit for the job seem the criteria for either getting it done, or abandoning the job in the middle of process.

I am glad that I have invested on the tools I have such as metal ramps, spanners, rachets, socket sets and blow torch, although sometimes it is a pain that I cannae find them in the shed when I need them urgently. My tools are mostly cheap ones from Amazon, but they seem work OK, but must admit, the sensor socket was not too impressive. It took out the top sensor alright, but the bottom sensor was needing something tighter grip and brute force.
 
And talking about Halfords Tools, yes, I think they are excellent value for money. I have a couple of the Advanced Socket Set and Metal Tool Chest from Halfords sales, and find them excellent tools.

The Advanced Socket set for the long bolts was especially useful for example, tightening the dinning table legs which had long bolts on the leg joins to the table, without which would have been impossible to tighten or take off.

I have bought tool sets only when they were big discount bargain sales.
 
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Checked the old sensors with DMM.

The top one reads 3.3 ohms
The bottom one is short = no reading
 
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