Hi, MOT just failed on emissions (lambda)? apparently 4 times over the limit anyone have any ideas what it might be? the garage said they can try any number of things, but can't promise any will fix it. they suggested replacing: front lambda, rear lambda, air filter, spark plugs... obviously replacing all these will cost a fortune... it passed the last MOT with no emissions issues at all ...any help most appreciated
Is there a check engine light? If you can get someone to scan it with a computer or look at the live data, you may get a clue as to what's causing it. You mentioned lamda, so there is a chance one of the o2 sensors are faulty (I think this would usually trigger a fault code, and you would see it in the live data) Catalytic converter can also be a cause but then you'd have to ask yourself, why did it go wrong? You can also check the air fuel ratio too, a clogged air filter or faulty MAP sensor can cause incorrect air fuel ratio. If your filter looks clean, then it's unlikely for that to be the problem.
Hi, thanks for swift reply. The garage don’t have a computer or software to scan. Agreed, there is no reason why the cat would have just died. I am going to take it on a long drive with redex in the tank, get some high revs. The garage have ordered new air filter and spark plugs. Hopefully this will do the trick. I don’t fancy replacing both the lambda sensors at £150 each if it doesn’t do the trick. any other suggestions? it passed with flying colours last MOT so strange for it to now have high emissions
Hi there First thing is where do you get your petrol? Steer clear of supermarket fuel. I would fill up with premium from Shell at the same time take out upstream lambda sensor which is located under the bonnet facing upwards which can be difficult to remove. To be done when exhaust is cold. You must have a good fit long series socket with plenty of clearance around the top of the sensor as the cable which has to be disconnected and pocked through above so as not to damage the lambda. Once out, do not touch it with a rag or oil but spray with electrical cleaner until clean. Replace and reassemble. Needs to be tight. You may have to clear the fault light several times before all is good. That's what I did to fix mine.
Hi, I always use Shell, never supermarket fuel. I don’t have a warning light on the dash but will ask the garage to try your method to clean the lambda, as I don’t have any tools anymore. Thanks
I've just recalled watching a video on Copen repair a while ago and remember hearing something about oil leaks from the valve cover dripping down onto an electrical connector and I think that was the o2 sensor. So you may want to check this connector as that could be the culprit. I did a reg check on your car out of curiosity and found that it's the Top Gear Copen! and I believe it's a JDM spec Copen and not a EU spec Copen as it's 2002, has it's rear fog in a different place and revs to 8.5k instead of 8k. The gov website also doesn't know what the co2 emissions are supposed to be. (EU Copen shows 151g/km) Anyway, thought it would be a good thing to check since I also saw something about a minor oil leak.
Hi, this sounds promising. I will ask the garage to investigate the oil leak as obviously this would cause high emissions if in the wrong place... the turbo doesn't always boost so I think the oil leak has something to do with that? the garage didn't realise these is a OD port near the throttle pedal, so will get them to plug it in an scan for fault codes - though there has never been a warning light on the dash. ...yes it has a strange rear fog and few other bits that make it different. Always thought it strange they needed heated seats in Japan.
So the garage fitted new air filter and spark plugs... no difference to the emissions. So its still a fail and they charged me £250... I’ve got the printout from the emissions test: its the FAST IDLE carbon monoxide (CO) that fails, 1.89% with a limit of 0.2% Thats 9 times the limit... surely something obvious must be wrong??? the second fast idle test passed CO with 0.18% Garage said could try a new cat! they were not interested in investigating the oil leak I have anyone got any ideas??? I will speak to another garage tomorrow as it seems silly to not at least investigate the oil leak ...they also assumed my car was a 1.3L not 0.66L engine and never even plugged it in to check for faults on the computer...
Hi I am not surprised having worked in the industry that garage knows how to make money by doing very little. The next garage first needs to plug your car in so to find the fault code. I am still convinced you need to investigate the lambda sensor as this controls the air intake information upon startup from cold. This would mean that your second start up showed a lower reading. Possibly the air intake sensor may be at fault but would only show up when fully warmed up. If you'd been given back the old spark plugs you could tell by the colour on the tips whether the fuel mixture was correct or not. They should be a light chocolate brown with no soot or oil. You need to either purchase or borrow a car diagnostic tool like a CAN OBD11 memoscan U480 (£15.00), which are quite reasonably priced for home use and can save you a conciderable amount of grief and money. Hope this is of help as our Copen is the same engine as yours.
Do you have any more info on the fail, there are 3 elements CO HC (hydro carbons or unburnt fuel) Lambda (how accurately the air fuel mix is to optimal (stochiometric)) Yeh , check out my vocabulary Very odd that it passed a 2nd fast idle test so I would think the cat is ok I assume it passed the natural idle? It would be much cheaper to try a new (the one by the turbo) lambda first rather than a cat, probably £80 and looks to be easy access on the 660 engine, Lambda's can get very slow with age, bit like me. Could be a case of just giving the car a good thrash on the way to the MOT, oh and try a different place, don't sound good value or helpful.
