OEM is most likely Bosch
Cant see the filter element causing these problems unless its knackered the afm
MOT Failure - Advice Needed
- Thread starter BilalSheikh
- Start date
OEM is most likely Bosch
Cant see the filter element causing these problems unless its knackered the afm
BilalSheikh
Member
Cheers guys. The car is regularly serviced on the right times but the major service was due soon. Anyways I dropped the car off with an Indie and he has now changed the following
I more thing which is left is the most difficult one. It is the turn indicators in the main beams. I cant figure out how to replace those bulbs. Any suggestions as this was one of the points. Apparently even though i can see they are yellow the MOT guy said they are giving a whitish tint.
EDIT: Just spoke to ALL PARTS they supplied a Bosch Lambda Sensor.
BTW i was amazed to see the price of unleaded today at 99.9 hope it goes back all the way
- Lambda Sensor
- Plugs
- Engine Oil
- Air and Oil Filter
- Anti roll bar bushes(They were squeeking a bit so i asked him to change all of them)
I more thing which is left is the most difficult one. It is the turn indicators in the main beams. I cant figure out how to replace those bulbs. Any suggestions as this was one of the points. Apparently even though i can see they are yellow the MOT guy said they are giving a whitish tint.
EDIT: Just spoke to ALL PARTS they supplied a Bosch Lambda Sensor.
BTW i was amazed to see the price of unleaded today at 99.9 hope it goes back all the way
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grober
MB Master
The main lighting units have large covers on the back secured by clips. If you remove the clips you will get access. You may have to remove the aircleaner assembly to gain access. If you mean the repeater units on the wings they are a push fit. Slide the unit forwards and unhook the rear. Don't damage the paintwork! I recommend the Haynes manual for a 1995 C class
http://www.haynes.co.uk/webapp/wcs/...ctId=13007&langId=-1&parent_category_rn=10215
http://www.haynes.co.uk/webapp/wcs/...ctId=13007&langId=-1&parent_category_rn=10215
BilalSheikh
Member
Just an update,
Although the leak is very minor it has not been sorted yet. But after having all the things mentioned above specially the lambda changed, i took the car to a garage and persuaded them to check the emissions.
Guess what it failed again. The same readings came up as mentioned earlier. They said that get the CAT changed. I spent a fortune on it last year. It had a warrenty on it for a year which expired in March. What do i do?
Can some one please explain to me how to interpret the readings which i posted earlier as even though Steve said the leak could be the cause for high CO and Lambda but the garage guy was saying with a leak the HC goes up.
Although the leak is very minor it has not been sorted yet. But after having all the things mentioned above specially the lambda changed, i took the car to a garage and persuaded them to check the emissions.
Guess what it failed again. The same readings came up as mentioned earlier. They said that get the CAT changed. I spent a fortune on it last year. It had a warrenty on it for a year which expired in March. What do i do?
Can some one please explain to me how to interpret the readings which i posted earlier as even though Steve said the leak could be the cause for high CO and Lambda but the garage guy was saying with a leak the HC goes up.
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kth286
MB Enthusiast
perhaps the lambda sensor wires are open circuit somewhere along the line.
They need to be checked for continuity back to the pins on the ECU plug.
Another important item for correct fueling is the coolant temp sensor, and it may have gone out of spec. It needs to be tested, but if failed is cheap.
They need to be checked for continuity back to the pins on the ECU plug.
Another important item for correct fueling is the coolant temp sensor, and it may have gone out of spec. It needs to be tested, but if failed is cheap.
bouncer
Active Member
- Joined
- Sep 20, 2007
- Messages
- 329
The lambda reading is the BIG clue.
Lambda greater than 1.03 = weak air fuel ratio.
The extra oxygen will be seen by the lambda sensor and it will attempt to richen the mixture thus the high CO at the tailpipe reading.
Fix the leak before you do anything else.
sTeVe
BilalSheikh
Member
Thanks i will get it fixed today and will take it for an italian tune up. Once done i will take it for MOT tomorrow. I will keep my fingers crossed.
But Steve how can the lambda sense the leak or more oxygen when it is in manifold and the leak is after cat. To be honest there is hardly a leak if you know what i mean.
Can you please give me any recommendation to which product i should go for in halfords or elsewhere as an additive in the petrol before the MOT.
But Steve how can the lambda sense the leak or more oxygen when it is in manifold and the leak is after cat. To be honest there is hardly a leak if you know what i mean.
Can you please give me any recommendation to which product i should go for in halfords or elsewhere as an additive in the petrol before the MOT.
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recycled
MB Enthusiast
I used wynns MOT emmissions reducer, after my car failed in the CO test. the lambda was Ok.
you can use that just to get you temporarily back on the road. For the lambda, you may need to look at the MAF as your A/F ratio seems to be wrong and fill up with the more expenive petrol for now.
This is what i did just to pass the emmisions
you can use that just to get you temporarily back on the road. For the lambda, you may need to look at the MAF as your A/F ratio seems to be wrong and fill up with the more expenive petrol for now.
This is what i did just to pass the emmisions
BilalSheikh
Member
Where can i get it. I just checked halfords website they dont have it.
They have this by the way. Probably what you are referring to but not the same name
http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_274571_langId_-1_categoryId_165750
They have this by the way. Probably what you are referring to but not the same name
http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_274571_langId_-1_categoryId_165750
recycled
MB Enthusiast
That was what i used. together with shell the (more expensive petrol ).
bought it on friday with about £15 petrol,drove it around and went on saturday morning.
CO emmisions went from 0.7 to 0.3 , but the lambda was already passed anyway.
It has some properties that reacts with the gases to reduce CO. a bit like the CAT.
I must stress it is only temporarily while it is in for the test and you need to find the cause of the problems
bought it on friday with about £15 petrol,drove it around and went on saturday morning.
CO emmisions went from 0.7 to 0.3 , but the lambda was already passed anyway.
It has some properties that reacts with the gases to reduce CO. a bit like the CAT.
I must stress it is only temporarily while it is in for the test and you need to find the cause of the problems
BilalSheikh
Member
Cheers yes i agree it would be temporary as i need to make sure it passes mot asap as the insurance doesnt pay out if there is no mot plus the road tax is expiring.
Thanks a lot for the advice. I will fill it with shell optimax as well.
Thanks a lot for the advice. I will fill it with shell optimax as well.
recycled
MB Enthusiast
next time, take it for MOT 4 weeks before it expires. you then have 4 weeks to complete any repairs wihout invalidating your insurance, as the old MOT is still valid.
that was what i did.
that was what i did.
BilalSheikh
Member
Yes that is normally what i do. Just had a baby and never had the chance to catch up with my appearance let alone the car.
BilalSheikh
Member
UPDATE: The car still wouldnt pass even after doing the following:
CO BEFORE= .7 AFTER .5
LAMBDA BEFORE = 1.078 AFTER 1.039
Took it to the people I got the cat changed from they told me the CAT is out of warranty by 2 months. They did say the back box sounds hollow and you will not get true reading because of it.
However the car did manage to pass on idle
. Now i have a year to sort out the problem with the emissions. So what should i include in the list
- Exhaust leak sorted
- Everything mentioned earlier(Lambda, full service)
- Wynns pre MOT emission reducer
- Bloody good thrashing on the motorway for about 40 minutes constantly from 5000 - bouncing off rev limiter
CO BEFORE= .7 AFTER .5
LAMBDA BEFORE = 1.078 AFTER 1.039
Took it to the people I got the cat changed from they told me the CAT is out of warranty by 2 months. They did say the back box sounds hollow and you will not get true reading because of it.
However the car did manage to pass on idle
. Now i have a year to sort out the problem with the emissions. So what should i include in the list- Lambda circuit trace
- Temperature sensor
recycled
MB Enthusiast
probably a new cat and maybe MAF. do not get a new merc CAT. wait until the next MOT and then get an after market one, like 2 weeks before
should cost about £150. start saving now. and use wynns or cataclean regularly. at least it works a bit. It did work for me.
Or just invest in an MOT friends station.
because my CO was high, i did put a bit more wynns and less fuel than recommended, so at one point i think i was driving on wynns. still worked for me though
should cost about £150. start saving now. and use wynns or cataclean regularly. at least it works a bit. It did work for me.
Or just invest in an MOT friends station.
because my CO was high, i did put a bit more wynns and less fuel than recommended, so at one point i think i was driving on wynns. still worked for me though
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BilalSheikh
Member
Cheers any recommendation on the after market ones as I wouldn't want to go for the same cat which has failed so quickly. Any manufacturers or suppliers?
PS: Any ideas why the lambda reading is still high?
PS: Any ideas why the lambda reading is still high?
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recycled
MB Enthusiast
Try from Ces UK. i have not failed on the lambda so no idea.
Any rubbish cat should pass if it is very new. it is the longetivity that causes the problem
depending on how long you are keeping the car. you can invest in an original cat £1k + VAt for merc or just keep an after market CAT lying around to bolt on before any MOT test
http://www.cesuk.com/ as directed to me by bosch UK
Bosch dealer
Any rubbish cat should pass if it is very new. it is the longetivity that causes the problem
depending on how long you are keeping the car. you can invest in an original cat £1k + VAt for merc or just keep an after market CAT lying around to bolt on before any MOT test
http://www.cesuk.com/ as directed to me by bosch UK
Bosch dealer
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bouncer
Active Member
- Joined
- Sep 20, 2007
- Messages
- 329
Just type high Lambda reading into google. . . . = air leak.
sTeVe
sTeVe
