Emissions MOT Epic Fail!
Discussion
How do people, 1st post and that,
My car (Renault Clio 1.4 Si year 2000) failed miserably on emissions on its MOT today, The CO topped out at 10.228% on the second fast idle test, where it only should have been 0.300% (max).
Both the Lambda sensors are less than 1 year old and the Cat is almost exactly a year old.
The mechanics said they had to leave the garage as their eyes were watering because of the emissions!!
I have read that ragging it before taking it to the MOT is a good idea, but I can't see how that would reduce the emissions as they are so high.
have scanned the Clio's failures below,
It's booked into Renault as the mechanics could not diagnose the problem on both of their computers.
anyone got any ideas? Im not looking forward to getting charged by Renault!!
BTW, looking at the report, it seems the Lambda read out passed the max allowed (ie it was under) but they have failed both of them, could this be a mistake or does the combination of the fails make it a fail if you get what I mean?
Thanks in advance
My car (Renault Clio 1.4 Si year 2000) failed miserably on emissions on its MOT today, The CO topped out at 10.228% on the second fast idle test, where it only should have been 0.300% (max).
Both the Lambda sensors are less than 1 year old and the Cat is almost exactly a year old.
The mechanics said they had to leave the garage as their eyes were watering because of the emissions!!
I have read that ragging it before taking it to the MOT is a good idea, but I can't see how that would reduce the emissions as they are so high.
have scanned the Clio's failures below,
It's booked into Renault as the mechanics could not diagnose the problem on both of their computers.
anyone got any ideas? Im not looking forward to getting charged by Renault!!
BTW, looking at the report, it seems the Lambda read out passed the max allowed (ie it was under) but they have failed both of them, could this be a mistake or does the combination of the fails make it a fail if you get what I mean?
Thanks in advance
Sir HC said:
The low lambda value indicated the car is running rich (very rich in your case), which explains why the technicians had to leave the test area !
Have you noticed your fuel economy reducing recently ?
Did the car pass its last MOT with the new Lambda and CAT fitted ?
Before I bought it (1 year ago) the cat had to be changed to pass the MOT. the first few months, the MPG was Sh*te and the under Lambda sensor was changed though this did not sort it, so the upstream sensor was changed as the car was cutting out as well. This was just after Christmas, and my fuel economy has been a lot better.Have you noticed your fuel economy reducing recently ?
Did the car pass its last MOT with the new Lambda and CAT fitted ?
The mechanic said it was still over fueling, maybe I got a faulty sensor or Cat put on?
It seems to have got massively worse between the first and second fast idle test, as if it was getting unhappy about something. Has it been serviced recently? The first test looked as if it might not have been far from successful and maybe clean plugs and filter would have seen you past. Second was obviously hopeless, perhaps you have a heat related sensor failure.
Munkeh said:
so a case of driving it har before the test isn't going to effect it then? they have checked over the whole car and think it might be a sensor problem (MAP or Coolant?) but their computer does not show anything.
If a sensor is gone, then the ecu wont have the necessary information to provide the fuelling to suit the conditions. It does sound like a temperature sensor has failed, so the car thinks its still cold, therefore pumping in more fuel to raise the temperature.I'd take it to a good mechanic to have a look, could be a number of things gone wrong.
it was last serviced in Feb (oil and filter change).
nothing has been changed on it since the up stream lambda sensor in January.
Im hoping Renault will find it (obviously) but I don't want to pay for their overpriced charges, however my mechanic said its best to get it done at renault as if they diagnose the problem, fix it but it fails again on the emissions, then renault should fix it for free?
nothing has been changed on it since the up stream lambda sensor in January.
Im hoping Renault will find it (obviously) but I don't want to pay for their overpriced charges, however my mechanic said its best to get it done at renault as if they diagnose the problem, fix it but it fails again on the emissions, then renault should fix it for free?
Munkeh said:
it was last serviced in Feb (oil and filter change).
nothing has been changed on it since the up stream lambda sensor in January.
Im hoping Renault will find it (obviously) but I don't want to pay for their overpriced charges, however my mechanic said its best to get it done at renault as if they diagnose the problem, fix it but it fails again on the emissions, then renault should fix it for free?
Is your "mechanic" a comedien too ?nothing has been changed on it since the up stream lambda sensor in January.
Im hoping Renault will find it (obviously) but I don't want to pay for their overpriced charges, however my mechanic said its best to get it done at renault as if they diagnose the problem, fix it but it fails again on the emissions, then renault should fix it for free?
And I think he's only saying its best to get it done at Renault, because he doesnt have a clue.
And if he thinks a main dealer is going to carry out work, then stand over it if it fails.....this guy must be on drugs.
Edited by stevieturbo on Friday 19th June 23:51
stevieturbo said:
Munkeh said:
it was last serviced in Feb (oil and filter change).
nothing has been changed on it since the up stream lambda sensor in January.
Im hoping Renault will find it (obviously) but I don't want to pay for their overpriced charges, however my mechanic said its best to get it done at renault as if they diagnose the problem, fix it but it fails again on the emissions, then renault should fix it for free?
Is your "mechanic" a comedien too ?nothing has been changed on it since the up stream lambda sensor in January.
Im hoping Renault will find it (obviously) but I don't want to pay for their overpriced charges, however my mechanic said its best to get it done at renault as if they diagnose the problem, fix it but it fails again on the emissions, then renault should fix it for free?
And I think he's only saying its best to get it done at Renault, because he doesnt have a clue.
And if he things a main dealer is going to carry out work, then stand over it if it fails.....this guy must be on drugs.
valve bounce66 said:
hopefully there will be fault codes stored to help at Renault,was there no warning lights on the dash ?
no warning lights or anything. you can smell the fumes when reversing though! Think Ive just got used to it!Well I will see what renault say, if its gonna cost a bomb, I will ring around, if not I will get them to do it.
If its a MAP or Temp sensor how much are we looking at for an independent garage to fit it?
Munkeh said:
valve bounce66 said:
hopefully there will be fault codes stored to help at Renault,was there no warning lights on the dash ?
no warning lights or anything. you can smell the fumes when reversing though! Think Ive just got used to it!Well I will see what renault say, if its gonna cost a bomb, I will ring around, if not I will get them to do it.
If its a MAP or Temp sensor how much are we looking at for an independent garage to fit it?
But diagnosing the problem might take time, especially if the people working on the car are idiots and dont know how to diagnose faults.
bertelli_1 said:
There is a risk your new cat is damaged now, also affecting emissions. Squirting that much fuel down the exhaust will severly shorten the life of a catalyst (thats why you should never bump start a cat equipped car too).
Good call, although the cat itself isnt the cause of the high emissions. There is a problem elsewhere.But now both might need fixed/replaced.
Well its waiting at Renault for its check on Monday now, When I was taking it there, I reversed with the window down and it was much worse than I have noticed it before.
Anyway, 'special offer' at Renault at the mo, diagnostic's check £19.99 (instead of their usual £90.00!!)
Thanks for everyones suggestions, I'll let you know what it is when (if) it passes the re-test.
Anyway, 'special offer' at Renault at the mo, diagnostic's check £19.99 (instead of their usual £90.00!!)
Thanks for everyones suggestions, I'll let you know what it is when (if) it passes the re-test.
This really shouldn't be that complicated. By far the most likely cause of a very rich mixture is a failed water temperature sensor putting out the resistance expected of a cold engine not a hot one. You can check the resistance yourself in 5 minutes with a £10 multimeter and a pan of hot water. No dealers required and anyway it probably won't show a fault code so a diagnostic test will be a waste of money. The system has no way of knowing the sensor is defective if it's putting out a resistance in a normal range but just the incorrect one for the actual temperature of the engine.
Sensor resistances are normally about 3000 ohms cold and 300 or so hot but no doubt the target values for your particular one could be looked up somewhere. It's not all that critical as long as the resistance drops by a factor of 10 or so when it gets hot.
SOP for a main dealer will be to do a diagnostic test, find nothing and then suggest replacing everything they can think of, starting with the most expensive, at your expense. You'd better make damn sure they understand NOT to do this without your prior approval. I wouldn't trust any of those feckless buffoons as far as I could spit a rat.
Sensor resistances are normally about 3000 ohms cold and 300 or so hot but no doubt the target values for your particular one could be looked up somewhere. It's not all that critical as long as the resistance drops by a factor of 10 or so when it gets hot.
SOP for a main dealer will be to do a diagnostic test, find nothing and then suggest replacing everything they can think of, starting with the most expensive, at your expense. You'd better make damn sure they understand NOT to do this without your prior approval. I wouldn't trust any of those feckless buffoons as far as I could spit a rat.
Anyone competent at diagnostics, can read any of the sensors with suitable equipment in seconds.
As useless as main dealers are....even they should be capable of doing this. Although as most dont understand the most simple things.....its probably over their heads...although they'l still charge you for wasting your time.
Any mechanic who blindly reads fault codes and leaves it at that, shouldnt be allowed near a car.
Sadly...thats what most seem to do.
As useless as main dealers are....even they should be capable of doing this. Although as most dont understand the most simple things.....its probably over their heads...although they'l still charge you for wasting your time.
Any mechanic who blindly reads fault codes and leaves it at that, shouldnt be allowed near a car.
Sadly...thats what most seem to do.
stevieturbo said:
Anyone competent at diagnostics, can read any of the sensors with suitable equipment in seconds.
As useless as main dealers are....even they should be capable of doing this. Although as most dont understand the most simple things.....its probably over their heads...although they'l still charge you for wasting your time.
Any mechanic who blindly reads fault codes and leaves it at that, shouldnt be allowed near a car.
Sadly...thats what most seem to do.
I find it funny when they plug the fault reader in, then come and tell me there is nothing wrong (it was the middle of winter, I was trying to avoid crawling around under the car in the rain). So the speedo not working is my imagination then! One gearbox speed sensor later and its all sorted. Sometimes you wonder if its company policy to leave common sense at the door when they put their overalls on.As useless as main dealers are....even they should be capable of doing this. Although as most dont understand the most simple things.....its probably over their heads...although they'l still charge you for wasting your time.
Any mechanic who blindly reads fault codes and leaves it at that, shouldnt be allowed near a car.
Sadly...thats what most seem to do.
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