Lambda slightly over.

Hi, My K11 has just failed it's NCT (MOT) with a Lambda reading of 1.05 when 1.03 is the max allowed. The tester guy said he tried to get it lower, but no go, and the engine temp was 87 C. He thought it might be an air leak. He also said people think dipetane works, but it doesn't. I drove to the testing centre at fairly high revs, and she runs well, and idles fine. Any ideas?
 
May have wanted a good run out ? probs a service or when was it last doen? , is there any leaks in the exhaust or has it had a exhaust ? (May find minor leak
How's the car normally used? I
Surprised they havent said cat ? Don t do that till last.And probs be best of to.get.Used over repo
 
OP
OP
Tornado
It sits unused for days on end, and gets the occasional run where it does reach operating temperature. I'm wishing I'd given it a sound thrashing before the test now, but a pinhole in the exhaust system would not surprise me.
 
Reason for askig is cold starts build up carbon, and such ,
May find the oil has a bit of a petrol smell to it , like old petrol aswell,
Had a few that have been sat for ages and found a service can do them a wonder if just a clean of the plugs
 
Only occasionally hits the middle of the temp gauge? I'm not sure what your circumstances are with how far you drive or whatever, but with me, the car would be off zero before I reached the end of my street, and before I hit the main road it would already be on middle.

Perhaps the same issue causing the fail, is causing it to take so long to get warm when you drive? Unless you literally just go to the corner shop 500m away? mine is a 1.0 litre engine they warm up quick usually
 
Only occasionally hits the middle of the temp gauge? I'm not sure what your circumstances are with how far you drive or whatever, but with me, the car would be off zero before I reached the end of my street, and before I hit the main road it would already be on middle.

Perhaps the same issue causing the fail, is causing it to take so long to get warm when you drive? Unless you literally just go to the corner shop 500m away? mine is a 1.0 litre engine they warm up quick usually
Tbh it can take up to 2 miles on my 1.3 even with a new nissan thermostat etc ,
but short trips without full temp will carbon up the combustion and exhaust
ANd probs be due a service ,may also find with short trip or not often used cars they should be serviced more often due to the cold starts and longer times in cold idle (rich mixture ) as it contaminate the oil and can wash the bores,
But as a quick fix probs a can of redex and clean or replace the spark plugs with ngk ones , let it get up to normal.running temp andn take it out on a 60 road and give it some, basically
 
OP
OP
Tornado
I think she warms up pretty promptly, but is rarely treated to a trip in a 60mph zone, never mind a motorway. The CO readings are 0.03 at low revs and 0.07 at 3K rpm, so does that suggest the Lambda 1.05 might be due to an exhaust issue? I bought it from a mechanic, he will take a look next week. Fingers crossed, I think a small weldable pin hole might be the best result. (Now, where did I put the Gun Gum? )
 
I think she warms up pretty promptly, but is rarely treated to a trip in a 60mph zone, never mind a motorway. The CO readings are 0.03 at low revs and 0.07 at 3K rpm, so does that suggest the Lambda 1.05 might be due to an exhaust issue? I bought it from a mechanic, he will take a look next week. Fingers crossed, I think a small weldable pin hole might be the best result. (Now, where did I put the Gun Gum? )
Exhaust pin holes can suck in unburnt oxygen & part restricted air filters can unbalance air/fuel ratios resulting in incomplete combustion.

Cheap supermarket fuels often lack the additives that keep fuel systems & combustion systems clean. All fuels have to meet a basic British Standard of 95RON for 'Premium' unleaded and 97RON for Super. Some exceed these RONS (Shell V-Power petrol is 99RON) and that is in addition to their additive packages. Redex is an ancient additive from the 1950s & adds nothing that is required in modern fuels & engines.

May I suggest a few fill ups with Super UL and do not add any further additives and a Italian tune up of a few tens of miles in lower gears to get the RPM up & dry out, blow out the combustion condensate lingering in the exhaust that never gets hot enough to dry out due to endless short journeys.

Quickly get it back for a free emissions MOT retest within 14 days of last test!

Good luck.
 
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OP
OP
Tornado
Free retest in the UK? It will cost me 27 euro here in the Emerald Isle but I have a month to get it sorted. I'll treat it to some better fuel with extra additives (Circle K Miles Plus?), look at the air filter and take it for a good run. Then get the exhaust system checked. Thanks for the replies, any further suggestions gratefully received.
 
for what it's worth, after you've given it a good run, take it to the MOT centre hot and just take the air filter out for the test. It won't do it any harm for a 30 minute test and that may help push the result the other way

Also I love the smell of a nice hot engine, you've been missing out on that smell for a while now go find a motorway and see if you can max it out then pull into services and give it a sniff lol :ROFLMAO:
 
Quote; “You smell that? Do you smell that?.10/40.. Napalm, son.

Nothing else in the world smells like that.

I love the smell of napalm in the morning; smells like victory”.

“Now look at the waves breaking both ways”.

 
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