Any Emissions Experts ?.

Discodog

My Freelander 1.8 petrol 2000 failed the NCT with the following values:

High Idle Lambda 1.07 should be 0.97 to 1.03
CO .61% should be below .3%
HC 195ppm close to fail at 200

I replaced the air filter & ran injection cleaner. On retest I got:

High Idle Lambda 1.08
CO .42%
HC 112ppm

It has done 100k & recently had a new head fitted so the engine is "clean". It has one Oxy sensor below the exhaust manifold & OBD 1. The tester said to change the Cat but how can that change the Lambda reading ?. Any advice would be much appreciated. I forgot to add that it runs really well with no hesitancy or misfires etc.

101sean

I'd change the Lambda sensor. Trouble is if it's been overfuelling it may have written off the cat.

There was a spate of cats being stolen off Freelanders and the like in the UK!

500sel

theres nothing wrong with your lambda sensor.
Get it to a garage and they will sort it out

Matt Simis

500sel wrote: »

theres nothing wrong with your lambda sensor.
Get it to a garage and they will sort it out

Based on what? Sometimes very strange resistance to changing a consumable, cheap(ish) part like the O2 Sensor on this forum from blow ins occasionally.

OP:
Is the year 2000 Freelander really OBD1? Thats shocking in its own right if true. OBD1 cars dont have post Cat sensors, so your car has no idea if the Cat is working. They also are generally crappier in everyway got to do with your engines performance, economy and emissions.
"The tester said to change the Cat but how can that change the Lambda reading ?. Any advice would be much appreciated. I forgot to add that it runs really well with no hesitancy or misfires etc. "
I think its worth pointing out the O2 Sensor reading result (hate the term Lambda, its confusing and pointless) on your NCT result is not your O2 sensor, its their one that they stick in the exhaust.
Ideally you should get the codes read. Possible causes are many for your poor emissions:

- Blocked or deteriorated Cat
- Misreading O2 Sensor
- Spark plug or ignition problem
- Vacuum leaks or Fuel Pressure leaks or malfunctioning injectors

johnos1984

A common fail with the k-series engine.

My advice is the following before taking it to a garage.

Check the exhaust for leaks as this can upset the reading, especially around the manifold. Have them fixed if there is any.

Secondly change the lambda sensor.

Perform a good service, new plugs, oil, filters and while your at it HT leads

The cat should be done if the others fail.

None of these is major and should extend the life of your car and give you more miles of happy motoring once the test is passed

Discodog

Thanks. I didn't realise that the Lambda reading was at the tailpipe. The strange thing is that my local main dealer said that he never sells any Lambda sensors - he implied that they never go wrong. But many manufacturers give them a life of about 50K & they are supposed to be fragile so might of been damaged during the head change.

I will try to check it over the weekend but it is not easy without a scope - I have a digital multimeter which won't react quickly enough.

500sel

Matt Simis wrote: »

Based on what? Sometimes very strange resistance to changing a consumable, cheap(ish) part like the O2 Sensor on this forum from blow ins occasionally.

Why change a part that there is nothing wrong with? Perhaps you should tell the op how to test the o2 sensor.
Blow in???? do you guys have a secret hand shake that you dont tell us blow in's about aswell?

Discodog

I spoke to a specialist garage & even they say that it might be difficult to diagnose & take a couple of days. It is tempting to replace parts that might not be broken because the cost is much less than testing.

I can virtually replace both the Cat & the Oxy sensor for the cost of the diagnostic test but the problem could still be the airflow meter or an injector.

Matt Simis

500sel wrote: »

Why change a part that there is nothing wrong with? Perhaps you should tell the op how to test the o2 sensor.
Blow in???? do you guys have a secret hand shake that you dont tell us blow in's about aswell?

a) You dont know there is nothing wrong with it, stop making out you do.
b) Why change it? Preventative maintenence, its cheap, easy to do himself etc. Why change spark plugs till there is a misfire, Oil till there is sludge etc? When changed, he can rule it out as an issue forever more. Im not recommending paying a dealership to change it, but its very cheap to do by the weekend mechanic.
c) I cant discuss the secret handshake.

crosshair1

Have seen O2 sensors destroyed from ethylene glycol after head gasket failure. Assume thats why your head was replaced.
You really need a diagnostic scan done to see if all the sensor values are ok, this would be the first thing to do.
Could also do with a leak test on the exhaust.

frex

Yep....do a leak check on the exhaust and on the intake, and then I'd look at the O2 sensor...they DO go wrong, and are not too tricky to test/replace (can be a bit rusted on, but generally come loose). You can test them yourself if you're handy with a multimeter.

Any problems I've had with O2 sensors have often also had poor idle quality, including engine hunting...does your engine ever "rev on its own" at idle? Its often a symptom of unpredictable fueling.

Last thing to touch would be the CAT

Discodog

frex wrote: »

.does your engine ever "rev on its own" at idle? Its often a symptom of unpredictable fueling.

No the engine runs superbly. No misfires, idles fine, & pulls well throughout the rev range. It definitely improved after changing the air filter & using injector cleaner. The improved test values show this. The head gasket leak was external. We examined the block & old gasket for any evidence of ingress into the block.

I can get a Bosal Cat for about €120 or a Eurocat for about €70 so it is tempting to change the Cat & sensor. Even the specialist admitted that, with OBD 1, it is almost impossible to test every possible cause & the only way to test the Cat is to eliminate everything else which costs way more than a Cat.

The NCT tester said "its probably the Cat" but he may of said that on the basis that a new Cat will tend to mask & mop up other problems. I would like to sort the problem fully but I have to balance the cost (it is an old car) against maybe fitting a Cat just to pass the test.

Discodog

I just have to add the bit of "advice" that I was given on a Landrover forum.

"Buy a cheapo new Cat. Remove the old Cat & use a cold chisel to smash up the innards so that they be removed via the pipe. Fit new Cat & pass test. Then remove new Cat & replace with old hollow Cat - gives better performance. Keep new Cat fresh for next test & refit when needed."

Clearly not a Green !.

500sel

Matt Simis wrote: »

a) You dont know there is nothing wrong with it, stop making out you do.
b) Why change it? Preventative maintenence, its cheap, easy to do himself etc. Why change spark plugs till there is a misfire, Oil till there is sludge etc? When changed, he can rule it out as an issue forever more. Im not recommending paying a dealership to change it, but its very cheap to do by the weekend mechanic.
c) I cant discuss the secret handshake.

I'm Not going to get into an argument with you on a subject that you have so little knowledge about ( This you have made quite obvious) there for don't bother replying

Discodog

I am just updating this thread to say that 500sel was right. I sought expert advice & was told to change the O2 sensor & the CAT. On retest my emissions went up & it now fails even on low idle !.

Now another expert is suggesting that it is the ecu. I am beginning to wonder if these guys just make it up on the spot & count the cash. I also suspect that I have been sold a dud CAT or that the O2 sensor is the wrong one.

CiniO

Lambda over 1, means pretty much, that your engine get wrong mixture. It's too much air for the amount of petrol.

Reasons for this might be different.
It might be any other sensor - say temperature sensor, or revolutions sensor, crankshaft sensor, etc...
You would need someone who would be able to check all of them sensors to find the problem.

crosshair1

Discodog,
You mention that experts have advised you to change this or that without solving your problem, are these experts remote:web based or real: physically inspected the vehicle.
This is not a rocket science problem, and can no doubt be rectified without undue expense on your behalf, but the workshop you use will have to be proficient in the use of diagnostics, oscilloscopes and emission testers.
I have had a rover 25 in recently with an emission failure due to a failed o2 sensor, once replaced the lambda readings returned but still couldnt reduce CO. Checked cat and it was burned out, fitted new, improved tailpipe emissions but not perfect until learnt values cleared from the PCM
You need to question your experts on those points!!

Discodog

It's much harder than rocket science which is the domain of experts. Yes my vehicle was inspected & supposedly tested by an expert mechanic. I have a good mechanical knowledge & I can tackle most jobs however emissions are different. I personally know two people who, on expert advice, paid a fortune for replacement ecu's only to find that the originals were ok & they are both mechanics !. I have approached a new set of experts that have all the equipment. Even they admit that it is a minefield. They have told me that they can test the output of all the sensors etc but that only eliminates some possible causes.

The maddening thing is that I have a vehicle that runs superbly with no misfiring, hunting or any sign of smoke etc. The engine is also pretty clean as a new head was fitted a few months ago. Unfortunately the trade know that this is an area where it is really easy to make a very quick buck.

crosshair1

Has this been on Diagnostics at all? Is it running in open or closed loop?

BrianD3

I feel you pain, it does seem as though a large proportion of those working in the motor trade can't/won't diagnose and rectify emissions problems in a logical way. Emissions problems often get fixed by someone stumbling on the problem or using "bolt on diagnostics" at the customer's expense.

And unfortunately, much of the advice given in this thread and in other emissions thread is no help. Making an uninformed guess is worse than saying nothing at all IMO. It's pretty clear that posters don't even have a basic understanding of what's going on e.g. in other threads, telling people to put "dipetaine" in the tank when a car has failed on lambda of >1.03 and nothing else when the most likely cause is a hole in the exhaust.

Seems to me as though there is a business opportunity for somebody to set themselves up as an "Emissions Specialist", if they marketed themselves well and got a name as being good they'd clean up. I asked a diagnostic tech who posts here but has emigrated to recommend someone like this in Ireland, they said they couldn't think of anyone that they'd recommend.

DublinDilbert

BrianD3 wrote: »

Seems to me as though there is a business opportunity for somebody to set themselves up as an "Emissions Specialist", if they marketed themselves well and got a name as being good they'd clean up. I asked a diagnostic tech who posts here but has emigrated to recommend someone like this in Ireland, they said they couldn't think of anyone that they'd recommend.

I think there would definitely be a business there alright. In the US it is quite common to get garages that just specialise in fixing emissions problems, which probably isn't surprising as this is the country that came up with the OBD1&2 standards.

Not sure if this is a good idea, but maybe a sticky in the "Tech" section with basic rules of thumb for diagnosing emissions problems? This should give people a better starting point than the usual advice of throw in some fuel injector cleaner + drive the crap out of it. It would be good if we could get some typical sensor voltages & waveformrs too, so people can have a reference when checking their own.

crosshair1

I'm not sure if its possible to have basic rules for emission faults without access to necessary diagnostic equipment.
If I have to repair an nct emission fail, the following is generally how I approach it.
1. 4 gas test to compare with NCT fail
2. Plug in diagnostics to car to check for fault codes or live data that may hint at a problem (not EOBD as it is extremely limited and ideally manufacturers interface)
3. Mechanical tests (vacuum, fuel press, exhaust/inlet leaks, compression,timing)
4. individual component tests with m.meter/scope
If I didnt understand or have the equipment to carry out any of those steps then I would not be in a position to rectify the fault.
Im not sure of the business opportunities in this field as a lot of workshops can get away with bolt on diagnostics as the components involved are relatively inexpensive spurious, myself I think the area of common rail diagnostics is more lucrative as the cost of parts is quite high for the bolt it on brigade.

Discodog

crosshair1 wrote: »

Has this been on Diagnostics at all? Is it running in open or closed loop?

It was supposed to of been put on diagnostics but I have not seen the results. Needless to say I now have little faith in the technician.

What baffles me is how he could change the O2 sensor plus CAT & make the emissions significantly worse - at least it passed on idle before. I wouldn't mind if there was some obvious symptom like a misfire but the engine performs really well throughout the rev range.

It doesn't help that it is OBD 1. It seems like vehicles of this age suffer from having more complex engines than the diagnostics of the time could cope with.

Before:

High Idle Lambda 1.08
CO .42%
HC 112ppm


After (with new O2 sensor & CAT)

Low idle CO .79%
HC 208 ppm

High idle Lambda 1.07
CO .62 %
HC 150 ppm

beam99

Your best bet there would be to find a garage that has a good freelander which is passing the emmisions and see if they are willling to swap parts over to find the problem with yours. Problems i have came across before are, the o2 sensor taking in air around the 02 sensor, gasket not seating properly. Faulty temp sensor,exhaust leak, Faulty airflow meter. Also fitted a new cat (after market) and to later find out the new cat was faulty,

shamwari

I feel very sorry for the OP here as he is getting advice from several here which is correct, but clearly hasn't worked.

I'm not going to attempt a diagnosis, but I will make the following observations:

Firstly, you also claim you car is OBD1, but I've just checked Autodata and it's listing an OBD2 diagnostic socket and fault codes. OBD2 became the norm on petrol cars from 2001, but most were compliant before this.

Assuming you are correct in that it is OBD1, the O2 sensor can only be checked with first generation scan tools (very rare), or a main dealer scan tool, or by scoping the output from the sensor itself. If this is done, a healthy sensor will see a voltage ramping between around 0.1 to 0.6 every second at idle. The problem is that some diagnostic "hot shots" know how to read an O2 from a scantool, but don't ask them to use a scope because they wouldn't know where to start I'd chance hooking and OBD2 scantool up to the car and seeing if you can read all of the live data.

Second, how is the car driving since the O2 sensor and the CAT have been replaced? Is it worse by any chance (particularly fuel consumption?)

Thirdly, was the O2 sensor you bought a "universal" one by any chance?

Fourth: has the coolant temperature sensor been checked, and it the car reaching normal operating temperature? I'd also check the wiring to the sensor, seen as the head was taken off. The output from the O2 sensor is ignored until the engine reaches in excess of around 65 degrees. If the coolant temp sensor is undersensing (i.e. reading too cool), the ECU will be fuelling the car as per a cold engine and this will screw the emissions and consumption up royally. This scenario can easily be confused with a malfunctioning O2 sensor

shamwari

BrianD3 wrote: »

It's pretty clear that posters don't even have a basic understanding of what's going on e.g. in other threads, telling people to put "dipetaine" in the tank when a car has failed on lambda of >1.03 and nothing else when the most likely cause is a hole in the exhaust..

Correct! A little knowledge is dangerous.

Also I would not put the dipetane stuff anywhere near my car.

Cosmo K

Looking at the figures, I'd say, the converter isn't doing what its supposed to do. Did you put in a genuine cat, or a spurios one?

Discodog

It is OBD 1. I believe the CAT that was fitted is a Bosal - a Landrover CAT would be impossibly expensive (€1000) & it failed on the original CAT.

It drives superbly with the new sensor which is supposed to be genuine Landrover. No noticeable increase in fuel consumption. I do not know if the engine temperature sensor was checked but the temp gauge is working fine.

The engine definitely reaches temp but the sensor could be misreading if it is a different sensor to the one that operates the temp gauge - need to check this.

Matt Simis

Discodog wrote: »

The engine definitely reaches temp but the sensor could be misreading if it is a different sensor to the one that operates the temp gauge - need to check this.

Was just about to mention that, it wouldnt be uncommon to have a Sender unit and an ECU Temp sensor as different units (or at the very least different wiring from one unit).

Discodog wrote: »

It was supposed to of been put on diagnostics but I have not seen the results. Needless to say I now have little faith in the technician.
What baffles me is how he could change the O2 sensor plus CAT & make the emissions significantly worse - at least it passed on idle before. I wouldn't mind if there was some obvious symptom like a misfire but the engine performs really well throughout the rev range.

You really need to get it Scanned and walk away with the results to do your own follow up. The responses you get here are based on experience of similar situations (despite what 500SEL says), but they arent in anyway specific to your car and would appear to be missing the mark.

On how it could have got worse after the new O2 Sensor (argh "Lambda") and Cat, either the problem, which wasnt those parts, got worse (vacuum or exhaust leak) or the new O2 Sensor was the wrong part.

If you want to continue the scattergun troubleshooting approach, Id check out the MAF myself. I would not however entertain the idea of changing the ECU without any diagnostic evidence to suggest this.

Max Power1

BrianD3 wrote: »

. Emissions problems often get fixed by someone stumbling on the problem or using "bolt on diagnostics" at the customer's expense.

.

Yes, there seems to be a lot of "diagnosticians" that would be more at home working with gregory house than with cars.

crosshair1

Just to clarify few things, these dont have a MAF, they have a map sensor.
Lots of posts about obd or obd2, this being a european vehicle will be either EOBD or not there is a difference.
I wouldnt get too excited about eobd data as its pretty limited anyways and certainly doesnt give anywhere near the full picture when interrogating an ecu.
There are plenty of interfaces to communicate with this vehicle irrespective of whether its eobd or not, KTS, Dec, Snappy launch etc most workshops will have one of those or something similar.
You also dont have any emission readings from anyone other than the NCT?
Did the workshop not check after fitting the o2 and cat to ensure they had fixed the problem?
I wouldnt pass much heed to the emissions being higher the second time round as the tester isnt going to go to the same rounds on a retest to heat up the cat and will have a fair idea if the problem is rectified or not
from initial readings.
2 things you could do yourself is leak check the exhaust and try and get a vacuum reading.

Discodog

Matt Simis wrote: »

Was just about to mention that, it wouldnt be uncommon to have a Sender unit and an ECU Temp sensor as different units (or at the very least different wiring from one unit).

If you want to continue the scattergun troubleshooting approach

There is only one temp sensor, it sends a signal to the ecu & the temp guage which is working fine.

I am not using a scatter gun. I employed a well recommended mechanic who told me that he would run all the appropriate tests - which clearly he did not do.

I am now doing a lot of research to select a good diagnostic centre. However unless we can test a vehicle ourselves we are at the mercy of the "expert" & ripe for picking.

The exhaust system has been thoroughly checked & there are no leaks.

Matt Simis

Discodog wrote: »

I am not using a scatter gun. I employed a well recommended mechanic who told me that he would run all the appropriate tests - which clearly he did not do.

Im saying the only responses you could possibly get here are scattergun TS type. Without even an OBC DTC and sight unseen, thats all you can expect!

shamwari

Discodog wrote: »

There is only one temp sensor, it sends a signal to the ecu & the temp guage which is working fine.

I thought those Rovers had a seperate Coolant Temp Sensor for the ECU, and a temp sender for the temp gauge on the dash. As a rule, the one for the ECU has two or more wires coming from it, whereas the one for the gauge is usually a single wire one. The attached shows the location of where the CTS is located. AFAIK, the one for the gauge is around the back of the engine near where the thermostat housing is.

shamwari

Also found the following for testing the coolant temp sensor from a Rover45 fitted with the 1.8 K series engine, which should be same / similar to that in the Freelander. An ohmmeter is required to test it by measuring the resistances across the two pins on the sensor at the temperatures specified: (disconnect the plug from the sensor before you commence reading the values. Also if the engine is running, this will put the engine manangement light on)

Read the values cold, and then with the engine at operating temperature, the values should be close to those for that temp in the table below.

Temp Resistance
0 C................5900Ω
20 C..............2500Ω
40 C..............1180Ω
60 C.............. 600Ω
80 C.............. 330Ω

Discodog

Ok guys a question. On a cold start my engine idles at about 1000 rpm. Once the temp gauge moves the revs drop nicely to the prescribed 750 rpm.

Does this not suggest that the engine temp & throttle position sensors are working ?.

beam99

It sounds like the temp sensor is ok, but to be 100% sure you need to look at the live data on a obd tester to see what sort of signal it is sending to the main ECU. The revs may go down when it warms up, but the ecu could still be getting a rich signal.

shamwari

Discodog wrote: »

Ok guys a question. On a cold start my engine idles at about 1000 rpm. Once the temp gauge moves the revs drop nicely to the prescribed 750 rpm.

Does this not suggest that the engine temp & throttle position sensors are working ?.

It depends on how the idle speed is controlled. On some older engines (The Toyota 4E-FE for example), water is pumped through the throttle body and this causes a waxstat to open & close inside it, controlling the cold / hot idle speed.

I don't know whether the Freelander is the same, but it should not be automatically assumed that the temp sensor is ok without having it tested, or the data read.

Where abouts are you based? Someone with a simple multimeter should be able to read the values I have previously given for the temp sensor.

JHMEG

Matt Simis wrote: »

Is the year 2000 Freelander really OBD1? Thats shocking in its own right if true.

Not really. OBDII/EOBD didn't become law till 2001 for petrols, and 2003 for diesels.

Matt Simis wrote: »

OBD1 cars dont have post Cat sensors,

Not true. Ever since emissions regs, esp to do with cats, came in cars have had them. I had several OBDI cars that had 2 O2 sensors, and I even had a pre-OBD car that had 2.

JHMEG

BrianD3 wrote: »

Seems to me as though there is a business opportunity for somebody to set themselves up as an "Emissions Specialist", if they marketed themselves well and got a name as being good they'd clean up. I asked a diagnostic tech who posts here but has emigrated to recommend someone like this in Ireland, they said they couldn't think of anyone that they'd recommend.

There are plenty of places that do it, and do it well. There's one in Wexford I know someone who had great results with. There is probably one in every county.

Emissions diagnosis is not a black art, far from it. Attempting to diagnose a problem with a shortage of tools on an internet forum with no shortage of tools only makes it seem like it is.

hasha

JHMEG wrote: »

There are plenty of places that do it, and do it well. There's one in Wexford I know someone who had great results with. There is probably one in every county.

Emissions diagnosis is not a black art, far from it. Attempting to diagnose a problem with a shortage of tools on an internet forum with no shortage of tools only makes it seem like it is.

hi jhmeg
My Freelander passed NCT except for emissions test. Changed the cat, O2 sensor, heat switch and ecu, still failed!!. Do you know someone in the Wexford area that can do a full diagnostic on a Freelander?
cheers

Discodog

hasha wrote: »

hi jhmeg
My Freelander passed NCT except for emissions test. Changed the cat, O2 sensor, heat switch and ecu, still failed!!. Do you know someone in the Wexford area that can do a full diagnostic on a Freelander?
cheers

What make of CAT did you fit ? It should be much easier to diagnose on yours because you have OBD 2 so you have a sensor before & after the CAT. I would sue any garage that changed that lot without diagnosing first.

hasha

They were second-hand parts!, in the end what did you need to do to rectifty the high emissions from your Freelander?

Discodog

hasha wrote: »

They were second-hand parts!, in the end what did you need to do to rectifty the high emissions from your Freelander?

I took it to a diagnostic centre in Galway. They diagnosed a misfire that was not obvious from the general running of the engine.

hasha

cheers man

hasha

Was it something simple like a dodgy HT lead or spark plug?

Discodog

hasha wrote: »

Was it something simple like a dodgy HT lead or spark plug?

Yep. One lead was damaged & it was arcing.

hasha

Hi lads, can anyone tell me, should the purge valve be working all the time on my 1.8 petrol Freelander '99? thanks

PADRAIC.M

At idle and deceleration

hasha

Thanks Padraic, mine dosent seem to work at all, even when I conect it directly to the battery. Is it faulty?