catalytic converter

zedhed · 26th June 2017, 21:14

well failed mot again today for the third time on emissions again.changed backbox and centre section so now it must be the cat and or lamba sensor.today went to grab a new lamba sensor,and got to grab the cat in the morning.my question is though,if the cat or lamba were faulty,wouldent the eml illuminate.it always seems to start smoking when it gets over 100 degrees and it does actually smell like a really hot kind of smell like the kind that the cat would emit,if you know what I mean.just getting really fed up now,this car does not want to see the road again.

SD1too · 27th June 2017, 08:25

Quote:

Originally Posted by zedhed

...my question is though,if the cat or lamba were faulty,wouldent the eml illuminate.

In theory, yes. It's said that engine oil in the exhaust will destroy the catalytic converter. Remove the lambda sensor and inspect it. Is it black, like an oily sparking plug?

Your MOT tester should be able to give you a print-out of the emissions test. The Hydrocarbons (HC) reading may well be high. Or you could get along to one of Arctic's local meetings where, I believe, a T4 is available.

Simon

HarryM1BYT · 27th June 2017, 08:46

Oil in a quantity, will wreck a cat. I have heard that Lamda sensors can be reconditioned by heating them to red heat with a blowlamp - but only try that if the item is scrap anyway.

philm · 27th June 2017, 08:53

You haven't actually said why on the emissions it has failed, could be for either of the reasons you have stated cat/lambda if the HC,s are high could even be a cylinder head valve not seating correctly not a very common problem but it is possible.it could also be any of the ignition components or on the fuel inlet side have you replaced the air filter if not worth a try to lean the system out a little,ask the tester if he can try the test at differing rpm limits and check results.
good luck anyway.

zedhed · 27th June 2017, 12:26

Problem was c0 level.it was 0.58.

philm · 27th June 2017, 13:21

Quote:

Originally Posted by zedhed

Problem was c0 level.it was 0.58.

Max is 0.30 so as long as lambda and hc levels ok,chances are it's the cat.

zedhed · 27th June 2017, 19:53

Well stuck a new cat and thread for the sensor seems different,so had to force it in basically.think it needs a steel washer though aswell.i give up

26th June 2017, 21:14	#1
zedhed Posted a thing or two zt saloon turbo Join Date: Sep 2015 Location: Tipton Posts: 1,461 Thanks: 1 Thanked 167 Times in 132 Posts	catalytic converter well failed mot again today for the third time on emissions again.changed backbox and centre section so now it must be the cat and or lamba sensor.today went to grab a new lamba sensor,and got to grab the cat in the morning.my question is though,if the cat or lamba were faulty,wouldent the eml illuminate.it always seems to start smoking when it gets over 100 degrees and it does actually smell like a really hot kind of smell like the kind that the cat would emit,if you know what I mean.just getting really fed up now,this car does not want to see the road again.

27th June 2017, 08:46	#3
HarryM1BYT This is my second home 75 Contemporary SE Mk II 2004 Man. Sal. CDTi 135ps, FBH on red diesel, WinCE6 DD Join Date: May 2010 Location: Leeds Posts: 17,273 Thanks: 2,160 Thanked 2,061 Times in 1,586 Posts	Oil in a quantity, will wreck a cat. I have heard that Lamda sensors can be reconditioned by heating them to red heat with a blowlamp - but only try that if the item is scrap anyway. __________________ Harry How To's and items I offer for free, or just to cover the cost of my expenses... http://www.the75andztclub.co.uk/foru...40#post1764540 Fix a poor handbrake; DIY ABS diagnostic unit; Loan of the spanner needed to change the CDT belts; free OBD diagnostics +MAF; Correct Bosch MAF cheap; DVB-T install in an ex-hi-line system; DD install with a HK amp; FBH servicing. I've taken a vow of poverty. To annoy me, send money.

27th June 2017, 08:53	#4
philm Loves to post rover 75 tourer Join Date: Jan 2017 Location: HEREFORD Posts: 269 Thanks: 7 Thanked 69 Times in 56 Posts	You haven't actually said why on the emissions it has failed, could be for either of the reasons you have stated cat/lambda if the HC,s are high could even be a cylinder head valve not seating correctly not a very common problem but it is possible.it could also be any of the ignition components or on the fuel inlet side have you replaced the air filter if not worth a try to lean the system out a little,ask the tester if he can try the test at differing rpm limits and check results. good luck anyway. Last edited by philm; 27th June 2017 at 09:39..

27th June 2017, 12:26	#5
zedhed Posted a thing or two zt saloon turbo Join Date: Sep 2015 Location: Tipton Posts: 1,461 Thanks: 1 Thanked 167 Times in 132 Posts	Problem was c0 level.it was 0.58.

27th June 2017, 19:53	#7
zedhed Posted a thing or two zt saloon turbo Join Date: Sep 2015 Location: Tipton Posts: 1,461 Thanks: 1 Thanked 167 Times in 132 Posts	Well stuck a new cat and thread for the sensor seems different,so had to force it in basically.think it needs a steel washer though aswell.i give up