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Seat Leon 1.4 2001 - MOT Emission Failure + EML Illuminated, codes P0030, P0036 & P0141 - Fixed #

Posted by Pete Mutlow on March 17, 2011, 8:49 pm

Year of Manufacture *: 2001
Engine Size and Code *: 1400cc
( Optional ) ECU Type: Bosch Motronic ME7 5 10
( Optional ) Scanner Used: ACR4 G2 and Crypton ACT 2
( Optional) Fault Codes: PO030,PO036 and PO141

Evening,

The story behind this vehicle is that the EML warning light came on a few weeks ago and then failed the MOT emission test a few days ago.

Now I think I have solved the emissions issue but have published it here in case it bears a relation to the EML problem. Without diagnosis, the garage suggested that the HO2 sensor be replaced to solve the 2 problems. It didn't. The sensor is NGK/NTK Broadband sensor. From memory, It failed because the Lambda reading was slightly too high although the CO was a pass but very marginal. I found the CO at 0% on both natural and fast idle with good HC's but O2 was about 2.8% on natural idle and lower on fast idle. On inspection, I found a blowing exhaust joint on the middle box which is the reason for high O2 and subsequent high Lambda value. Customer has been advised to get that repaired and hopefully it will pass.

The second problem on which I am stuck are the fault codes as follows: They all relate to the heating element of the Broadband HO2. PO030 - Bank 1 Sensor 1, PO036 + PO141 Bank 1 Sensor 2. There are 5 wires to the sensor and read as follows: 2 heater wires = 2.95v (blue and yellow), Earth wire = 2.95v (Black), Measurement cell = 2.5v (grey), Pump flow = battery voltage (white). Now I would have thought the earth wire would have been below 0.25v and did consider stuffing it to earth but thought I should exercise caution on a new sensor which cost the customer about £150!

So, I would be grateful on what you think about these voltages and how I should remedy the situation. Apologise for long post but needed to make sure you have all relevant info.

Regards

Pete M

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Bryan Smith on March 17, 2011, 11:26 pm, in reply to "Seat Leon - MOT Emission Failure + EML Illuminated"

Hi Peter,
I have not got all the info with me at the moment but I recently tested a Golf with a 1.4 AXP. From memory the wires from the sensor change colour at the multi plug. I seem to remember that the heater is the same as a zirconia type ie: 12V and are the white and grey wires. The ref voltage (nernst cell?) was about 2.5v at the black wire. I think the pump is fed by the red and yellow wires but these change polarity depending on which direction the pump is working in order to stabilise the ref voltage (easily checked with a scope).
Hope I got that right but someone will probably correct it if I'm wrong.
Regards, Bryan.

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Pete Mutlow on March 18, 2011, 12:04 am, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Peter Mutlow

Evening Bryan,

Thanks for your input. This vehicle is also an AXP engine and the colour codes were reproduced from I think the NTK/NGK web-site. Did about an hour or so researching this but cannot be sure. All measurements were taken from the sensor wires. Now here is the strange thing, the sensor has 5 wires but is connected to a 6 wire connector to the loom. Both connectors have 6 pins so there is a con-joint in the connector. I initially measured the voltages on the 6 wire loom cable and found that the "6th" wire contained a fluctuating voltage of about 0.5v to 2v @ about 1 hertz. This complicates it more for me but could this be the changing polarity you are talking about? I put my hand up and admit that electrics is a weak point for me..

Regards

Pete m

PS...shame that the spell check is not English but American!!

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Bryan Smith on March 18, 2011, 9:06 am, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Message modified by board administrator March 18, 2011, 3:19 pm

Hi Pete,
Vivid shows 5 wires but I have a leaflet from a Snap On seminar which shows a 6 wire terminal (for a Bosch LSU 4.9) but has no colour code for term 5. I do remember that the colours changed at the terminal. I can't remember what AD has as I am not in workshop at the moment. Will have another look at what I have during the day. In the meantime have a look at this. It shows the ref: voltage as 450mv but I am sure that this sensor is about 2.5V.

http://wbo2.com/lsu/lsuworks.htm

Looking at that it seems that it is probably the red wire which switches pos/neg and the yellow may be the feedback? A bit of probing with the scope and I was able to work it out but I am also a bit weak on electrics.
This give limited info.

http://www.bosch-motorsport.de/pdf/sensors/lambda/LSU49.pdf

HTH's, Bryan.

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Bryan Smith on March 18, 2011, 4:55 pm, in reply to "Seat Leon 1.4 2001 - MOT Emission Failure + EML Illuminated, codes P0030, P0036 & P0141 #"

Hi Pete,
According to AD, terminal 3 (heater supply) should be blue/yellow and is batt volts from fuel pump relay via fuse 43. This also supplies HO2S B1 S2. If you only have 2.95v at this wire that may explain DTC's for both sensors? Term 4 should be green/yellow and is the PWM earth for the heater.
because of the change of colours it's a bit confusing but I think the feedback was the yellow wire from the sensor and perhaps it was 450mv not 2.5v as I thought?
HTH's,
Bryan.
PS. Just read that if the heater is not working that will clog the diffusion gap and trash the sensor.

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Pete Mutlow on March 18, 2011, 9:39 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Peter Mutlow

Hi Bryan,

Many thanks for your time and effort in helping me to get to the bottom of this. Yes the colour coding does make the whole thing confusing, however I think the main issue here is a lack of earth on terminal 4. I will make arrangements to have a look at the vehicle next week when I am in the area and hope he passes the MOT test in the interim which is his main concern. Many thanks again..

Regards

Pete M

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Bryan Smith on March 19, 2011, 10:20 am, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Bryan Smith

Hi Pete,
Bear in mind that as it is PWM you will not get zero volts when running. Also, both O2S have seperate earths but common feeds. The ECM pin Nos' for the earths are 1 for S1 and 13 for S2.
HTH's,
Bryan.

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Pete Mutlow on March 19, 2011, 10:33 am, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Peter Mutlow

Thanks Bryan...I am now going to display my total ignorance... Can you explain in simple terms what PWM stands for?

Regards

Pete M

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Kevin Apps on March 19, 2011, 2:13 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Kevin Apps

Pete
Pulse Width Modulation. Use a scope.
Kev.

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Pete Mutlow on March 19, 2011, 3:43 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Peter Mutlow

Thanks Kev. Will have to do some homework on that with pico to see what I should be looking for.

Things have took a turn for the worse. Customer has had the exhaust joint seen to and took it back for an MOT and now "It's twice as bad as it was before" The original readings on the MOT was 0.28 and 0.30% CO and deemed a pass. It failed on a slightly high Lambda reading. On my first post the CO at fast idle was 0% when I tested it. Maybe because the heater element is not functioning, the sensor has not warmed up enough to do its job properly. I have a feeling I am being optimistic !

Regards

Pete M

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Dave Hill on March 19, 2011, 5:11 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"

Hi Pete

This thread has some discussion on the subject of PWM.

http://members5.boardhost.com/ukautotalk4/msg/1234564228.html

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Bryan Smith on March 19, 2011, 8:39 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Bryan Smith

Hi Pete,
You could also test with a meter that measures duty cycle. The last one of these I played around with had a duty cycle to S1 of about 58% (which is correct according to AD) and S2 (narrow band) was about 10% but I was not able to confirm if that was correct or not. If you want to use the scope set it for about 20V/250ms.
From reading your original post again I see that you have batt volts to at least one of the terminals but I think you need to confirm whether that is the heater supply or not. As I have said, it seems odd that codes point to both heater elements and the only thing common is the supply. Another question is, is the ecm going into closed loop? If it's not happy with the heater circuit it may not.

Dave,
I have just tried searching for an excellent thread on testing O2 heaters which I think you were involved in. I think that that thread would help Pete if you are able to find it.

Regards, Bryan.

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Andrew Kevans on March 19, 2011, 9:55 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Andrew Kevans

I had the same problem and fitted an NTK sensor car came back a day later ordered genuine sensor from T.P.S fault cured?HTH

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Pete Mutlow on March 19, 2011, 10:11 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Peter Mutlow

Thank you all for your interest and help. I intend to spend an hour or so doing a bit of homework based on your helpful tips before revisiting the vehicle.

If I understand PWM correctly it means, in simplictic terms, the frequency of switching remains the same no matter what is happening.

According to the NTK/NGK site, the battery voltage recorded on the sensor white wire was to the pump and I was only getting 2.95v on the green and yellow sensor wires which are to the heater. The difficulty I have is not knowing with clarity what I should be seeing. I will have a look further down stream on the wiring loom (with its different colours) and try and equate with the info I now have. I also do not understand why I have 6 loom wires going into a 5 pin socket. Also, why the "6th" wire is switching from 0.5v to 2v. Hopefully all will become clear on my next visit..

Interestingly, I have noted that the ECM will fault the heater and produce these DTC's if it does not see a closed loop situation within 30secs of start up based on the ECT sensor. So maybe the heater circuit is OK but the ECM is not seeing it due to a different fault.

Finally, should this heater be "on" all the time? I think not and remember my scanner telling me that the heater was "off" at some point in my investigations. On the next visit, I shall watch it carefully from start up.

Again, thanks for your interest but my gut feeling tells me I am out of my depth on this one but we will see..

Regards

Pete M

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Pete Mutlow on March 19, 2011, 10:18 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Peter Mutlow

..Thanks Andrew for that, it adds another dimension to the problem! Need to convince myself and then him that his £150 sensor is rubbish and needs to spend a whole lot more for the genuine article

Regards

Pete M

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by aidan on March 19, 2011, 11:28 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Aidan Birley

Pete

the only good news is the genuine sensor may well be cheaper !!!

What does the sensor show on Live data ?

may be worth checking heater circuit with scope + amps clamp.

with emission fault may be worth some basic checks like air leaks / compression / manifold vacuum / throttle body clean etc

cheers aidan

cheers Aidan

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Dave Hill on March 20, 2011, 7:40 am, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"

Hi Pete

Here is a link to the thread that Bryan mentions (thanks for the kind remark Bryan). The DTC is the same as yours too.

http://members5.boardhost.com/ukautotalk4/msg/1263154567.html

You are right, the frequency that the cycles start & finish is fixed & it is only the ON & OFF ratio that is adjusted by the control unit in it's efforts to aportion the correct amount of current to drive the consumer.

Think of a heating element that, with a constant supply & ground, would draw 10 amps. If you then rapidly switch the circuit (supply or ground) on and off, then you can regulate (modulate) the current flow. If the the width of the rapid ON pulse is for example 50%, then half of the current will flow (5 amps in this 10 amp example). If an ON period of 20% was applied, then 2 amps would flow.

This is possibly over simplifying the subject, as heat is a factor when considering resistance, which is another reason why I like to look at these circuits whilst in operation with the scope.

In your case Pete, I wouldn't expect the PCM to set a heater circuit DTC unless it detected one!

HTH

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Michael Whitworth on March 20, 2011, 9:01 am, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Mike Whitworth - Administrator

Hi Pete,

I find it ironic that nearly all your replys to other techs ask for all four gas readings even if it is a rear wheel bearing fault

, but on your post about an emiissions failure you only give us snippets from the gas analyser.

Appologies if you feel I am taking a pop but it did make me chuckle.

Anyhow to the subject in hand. I am surprised to read you have never come across the term Pulse width modulation before, as for many years now the VMs have used this method of controlling actuators and solenoids in allsorts of applications.

Turbo boost control, EGR control, intake butterfly control to name a few.

Dave Hill puts it very well in his desription further up , I would not say he has over simplified it more put it into a nice easy to understand way without complications such as resitance and temperature. There are some things you don't need to know so why complicate it.

.

Personally I agree with you that you need to sort the problem with the heater circuit before doing any further testing on this vehicle and from what I have read in your other posts you are not out of your depth with this one but you seem to have taken a knock to your confidence and just need a shove in the right direction.

Forget testing this sensors signals with a voltmeter as that will not reveal much of any use, these sensors generate very low current which is monitored by the ECU and can only realy be veiwed on a scope if you have a very expensive clamp like the one in the piccy below. Confirm integrity of the wiring to the sensor and test the heater circuit the same as you would on a 4 wire std sensor bearing in mind the PWM. A scope and a low amps current clamp is usually best for this.

Use livedata to evaluate sensor operation group 30 upwards, group 33 gives a represntative display of the sensors output in block 1 & 2.

It wouldn't surprise me if the new o2 sensor is faulty though, I always fit Bosch if OE or Genuine from TPS,

HTH,

Mike

M.O.M. Miserable Old Manc

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Bryan Smith on March 20, 2011, 4:43 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"

Sorry. Now moved to the correct place.

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Bryan Smith on March 20, 2011, 4:47 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Bryan Smith

Hi Mike,
This is probably muddying the waters a bit as it seems likely that Pete has a heater fault. As I understand it, although you are correct in that the output signal cannot be measured easily, it is possible to test the pump circuit reaction to this signal. The current will flow in a different direction depending on whether O2 is being pumped in or out, and this is quite easy to see on a scope. My problem is that I cannot remember which wires to test (as mentioned, not helped by the colour changes at the terminal) but with a bit of "playing around" it is fairly obvious. I know this isn't testing the signal output but it does allow you to see a reaction when you force a rich or lean mixture.
Regards,
Bryan.

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Kevin Apps on March 20, 2011, 5:42 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"

Pete
For what it,s worth i only fit genuine sensors.
I know 2 really knowlegdeable VAG guys who have had problems with non genuine O2 sensor,s and heater resistance looks OK but genuine sensor get,s a FIX.
Kev.

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Pete Mutlow on March 20, 2011, 7:15 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"

Evening all,

Once again many thanks for your responses. I appreciate the time and effort you have put in for me on what I feel is not a straightforward problem.

The customer doesn't really care about the EML being illuminated and will not spend a lot of money to fix this. His prime concern is the MOT Emission failure and this will be my priority. He and the garage assumed that the two items were related which is why I posted on both subjects. I would have assumed and please correct me if I am wrong, that the heater circuit would not create an MOT emission failure IF the HO2 sensor was in closed loop at the time of testing (assuming of course that the CAT was properly lit up and functioning correctly). I was with the vehicle for a long time time and I am assuming the HO2 sensor was heated naturally by the exhaust down-pipe. It certainly was in a closed loop situation which is why I got a max of 0.1% and 80ppm HC. The failure was down to a slightly high Lambda reading which I put down to a blowing exhaust. If I revved the vehicle at about 3500rpm (outside MOT testing specs) the Lambda reading would be within limits. So it might have failed again because the garage did not allow time for the HO2 sensor to get heated enough and was not in closed loop. I will see on my next visit. I know the customer will not pay for another sensor just to get his EML extinguished but I am interested enough to find out the cause of this problem.

Mike. Yes you are right. When I look at other peoples problems posted on here, then I do want to see what the emission figures are if applicable. I do not normally have trouble with emission problems and did not post the full details of them because I thought I had it sussed with the blowing exhaust which is why I only gave it the briefest of detail. As far as the PWM issue is concerned you are again right and it is a "black hole" that I have in my knowledge which I must try and remedy. Nice to get a chuckle from a M.O.M. though!

Regards

Pete M

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by aidan on March 20, 2011, 8:38 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Aidan Birley

Pete

My thoughts are that if the ECU is not happy with the O2 sensor heating circuit ( i.e fault code ) it will quite possibly ignore any o2 information from it and work in a default mode.

I don't know the ECU strategy on this particular model, but have certainly experienced this on other brands.

I think you have no option but to address the heater circuit fault code.

Cheers Aidan

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Michael Whitworth on March 20, 2011, 10:50 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Mike Whitworth - Administrator

Hi Brian,

There may well be something in your method of observing the direction of flow of the pump current but it is not something I have practiced or felt the need to do. Having said that I might just do a bit of research next chance I get.

Hi Pete,

I have to agree with Aiden! With any emissions problem it is most important that ALL the lambda sensor is working correctly as the internal heat from the heater will get the Sensor Up to temp Quicker and keep it there. Where as relyiing on external heat from the exhaust stream is not consistant. There are guidelines for Testers to follow when carrying out an emissions test, usually instructions from the gas analyser, and if it fails when these guide lines are followed then its a fail. irespective of whether it would have passed if they had cruised it for another ten mins and then carried out the test.

Modern O2 sensors heat up very quickly and I have observed engines running in closed loop within minutes of cold starting, thats how good they are.

Do not allow a tight ***ed Customer to dictate to you, If he wants a pass and he wants you to achieve that it needs the heater circuit faults sorting.

Just my honest opinion.

Mike

M.O.M. Miserable Old Manc

Re: Seat Leon - MOT Emission Failure + EML Illuminated

Posted by Bryan Smith on March 21, 2011, 6:12 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Bryan Smith

Hi Mike,
Here are the images from testing an AXP Golf HO2S pump current flow. After giving it some thought I am sure that these were taken from the red and yellow wires. I think it would have to be 2 wires because of the reverse of polarity. I did not save the whole movie but as you can see it's not a lot different from the output signal of a normal zirconia sensor. I know it's not ideal but in the absence of a suitable amps clamp it has worked for me as can be seen by the after and before images from the same vehicle.

After Replacement.

Before Replacement

Regards to all.
Bryan.

Seat Leon - Update

Posted by Pete Mutlow on March 21, 2011, 7:13 pm, in reply to "Re: Seat Leon - MOT Emission Failure + EML Illuminated"
Peter Mutlow

Evening All,

In the interim period of my last visit and todays visit, the customer has spoken with the main dealer about the problem. They have told him that it would be "improbable" that an after-market sensor would solve his problem and the first thing they would do is bin it.

However, I pitched up again today and found the following:

1) An additional fault code was present which was PO134 - HO2 sensor circuit.

2) I watched the heater operation on my scanner from cold and at all times remained "off".

3) The 02 content was down to normal at about 0.6% at idle and a bit lower at fast idle. Lambda reading was within MOT limits at 0.99. The leaking exhaust joint had been fixed.

4) The CO level at fast idle was now 0.4% and on a second run at 1.4%.

In view of the foregoing, I took the easy way out, the customer is happy to invest in an OE sensor. This decision was based on what the customer had been told by the stealers and the opinions voiced in this thread. Also, if the new sensor did not fix it, then the fault as I see it would lay in the wiring loom or ECU which is something I am not comfortable to be involved with. Also, the MOT expiry date was getting close and the extra time spent with me testing further and posting findings and awaiting helpful hints would push it past the MOT expiry date.

Now normally I would test an expensive sensor to the Nth degree before replacing, but in this case due to the complexity of the situation, I have made an exception to the rule. The customer will advise me of the outcome.

Finally, thanks to all for your helpful advice and also Dave Harney who rang me this morning.

Regards

Pete M

Re: Seat Leon - Update

Posted by Jon Morgan on March 21, 2011, 8:13 pm, in reply to "Seat Leon - Update"
Jonathan Morgan

I had a 2003 1.6 Golf in today with the MIL illuminated - fault of O2 S2 electrical fault in circuit.
I hooked it up to the gas analyser, engine at 90C & at fast idle it had a CO of 1.5%.
While still connected to the gas analyser I cleared the DTC & watched the CO drop almost intaneously down to 0.02%, this is a regular occurence with VAG software.
The ECU likes everything tickety boo or it defaults into a strange rich mixture mode.

I also had the runaround as you are describing above, with a Bosch O2 sensor on a 2.0 Golf.
I fitted a new Bosch sensor, after which every couple of weeks it would return with the MIL on & a fuel trim fault logged.
After much testing & getting nowhere, I binned the Bosch sensor & replaced it for a genuine VAG (Bosch) sensor - it has been back for servicing etc since with no repeat of the fuel trim fault.

We now only fit genuine sensors across the board, we've been legged up to often with AMM's, coolant temp senders, O2 etc....

hth,

Jon.

Re: Seat Leon - Update

Posted by Pete Mutlow on March 23, 2011, 7:48 pm, in reply to "Re: Seat Leon - Update"
Peter Mutlow

Evening All,

Not good news on this one I'm afraid. Customer found out that he had been supplied with the wrong sensor. They refunded his £150 and said that they can provide him with the proper article for an extra £30 but it would have to be ordered. He had somehow via friends in the right places managed to secure a main dealer sensor for a trade price of £91! The connector was completely different to the one he had been supplied but identical to the original sensor he had discarded in the first place. He could only describe it as a lot bigger with more "gubbins" inside. On the way to the MOT station feeling very optimistic he had a scrape with another car. This was followed with a fail with the "emissions going up and down". On the way back feeling rather deflated the car broke down and here is an interesting thing: According to him it has done it before when the oil gets low and it acts as a fail-safe. I have not heard of this before..have you? Anyway, he refilled it with oil but it would not start and it was towed home whereupon it started on first turn of the key. Now apparently he has been told that this model uses a lot of oil and its a known problem. I am sceptical of this and the fail-safe option. Anyway car is now having bodywork repaired and I have volunteered to have yet another look when he gets it back. I will keep you informed.

Regards

Pete M

PS. EML did not extinguish when he put fitted new sensor.

Re: Seat Leon - Update

Posted by aidan on March 23, 2011, 9:49 pm, in reply to "Re: Seat Leon - Update"
Aidan Birley

Pete
If this is same set up as golf 1.4, check the oil separator unit on breather system, If clogged will cause high oil consumption.

May even help emissions.

Cheers Aidan

Re: Seat Leon 1.4 2001 - MOT Emission Failure + EML Illuminated, codes P0030, P0036 & P0141 #

Posted by Bryan Smith on March 31, 2011, 1:12 pm, in reply to "Seat Leon 1.4 2001 - MOT Emission Failure + EML Illuminated, codes P0030, P0036 & P0141 #"
Bryan Smith

Here are some more captures of the pump current flow from a known good AXP Golf broadband HO2S. They were taken from the red and yellow wires on the sensor side of the multi plug. The first is at idle, the second at fast idle. The third is after a "blip" on the throttle which clearly shows the PCM reaction to the extra fuel and the time taken before recovery. Bear in mind that is not the sensor output but the PCM output to the pump. These captures show the amplitude lower down the scale than my previous one but I think this is just because the - and + were reversed.

Hope this is of help to someone.
Regards,
Bryan.

Re: Seat Leon 1.4 2001 - MOT Emission Failure + EML Illuminated, codes P0030, P0036 & P0141 #

Posted by Pete Mutlow on March 31, 2011, 7:06 pm, in reply to "Re: Seat Leon 1.4 2001 - MOT Emission Failure + EML Illuminated, codes P0030, P0036 & P0141 #"
Peter Mutlow

Thanks Bryan and Aiden. Customer has not contacted me yet for a return visit. I have the feeling he is going to get it sorted when he is having the bodywork attended to. We shall see,

Regards

Pete M

Fixed #

Posted by Pete Mutlow on April 8, 2011, 8:12 pm, in reply to "Re: Seat Leon 1.4 2001 - MOT Emission Failure + EML Illuminated, codes P0030, P0036 & P0141 #"
Message modified by board administrator April 11, 2011, 4:27 pm

Evening All,

MOT Testing station confirms that the car passed its MOT. So, the problem was due to an incorrect HO2 sensor fitted. Customer did promise me he would let me know how it got on but looks like he couldn't be asked which is dissapointing..

Thanks to you all for your help.

Regards

Pete M

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