Failed MOT emissions test on bangernomics car, solutions?

Our 96 Toyota Corolla 1.3i had it’s MOT today, all okay apart from emissions, CO and hydrocarbons were too high so it failed. I guess we just don’t use it enough these days (less than 2000 miles in past year) but despite this we love it, worth nothing but always starts and nice to drive still. Until this nothing has gone wrong. We’d want to keep it but know it’s not really worth spending any major money on.

Bloke at MOT station said try putting some posh petrol in, and a fuel additive/cleaner, take for an Italian tune up by thrashing it for a good few miles in lower gears and then bring it back for a re-test on Monday. Any recommended additives or other advice/tips? Cheers

Terraclean would get it through.

BG 44K fuel additive would do it but you won’t get it in time to make a difference.

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Likely a sensor. Get codes read?

Advice from bloke at mot station is spot on, two years running my car has failed on emissions, this year well out, fuel additive and a damn good thrashing, service, filters and it passed

Molgrips, he said sensors all fine, no codes showing problems, said rest of car was really good for age.

Take it in properly warmed up, unless you’ve a decent run to the MOT station it might have been tested colder than ideal which could affect the mixture. Maybe.

Italian tune up would be my first thought given how little millage it’s done recently..

You don’t need to be mechanically unsympathetic, just stay in gear longer change gear a lot later and give it a good long drive.

Depends on your gear box ratios, you don’t want to be red lining it, but cruise at higher revs than you would normally.

Also as above, make sure its had a good run and up to temperature pre test.

Yes, MOT station is only a mile away so that probably didn’t help driving up there this morning, not warmed up and running rich still probably

Petrol or diesel?  I’m guessing the former.

I had a Corolla of that vintage as a courtesy car once.  One of the most hateful things I’ve ever driven.  Personally I’d be thanking the stars and replacing it with something that wasn’t 22 years old.

Yeh a 1 mile bimble on a stone cold engine won’t give it chance to warm up properly.

Tank of shell V power new air filter and a really good thrash.

Cougar – Petrol (1.3i), it’s great, yes not cool, old & battered, boring old farts car etc but does still go really well, always starts, runs quiet and nothing has gone wrong until this, 2 bikes fit in no problem. Not bad on fuel too and cheapish insurance. If we can keep it going for a few quid for another year, why not? It’s a pool family car mainly used by kids when they come home, saving our newer ones, who gives a toss if it gets trashed.

What’s not to like?

New set  of spark plugs  would help as well

Or get the existing  ones  really  clean and correctly  gapped.

Maxtorque  is  the  man for  car tuning, but looking at those  numbers a run through with no air filter  might alos  give  you lower CO

The Hc numbers  will  improve with a hot engine , so 15min  drive with load on engine ( load = more fuel .- ,more fuel = more  heat ) so abit of left foot braking or accelerate / brake accelarate  again should lean out the mixture.

Reminds me of

Long hard drive, properly heat soak the motor, maybe keep it in 4th rather than 5th on motorway.  Try MOT again.

As other said, service, posh petrol and a thrash. Change the air filter and spark plugs as well as the oil and filter.

Could also be burning oil if its not warmed up, old cars leak down the valve stems whilst not running and it takes a while for it all to burn off.

My only worry would be the cat, between that and the lambda sensor it should be hard to fail an MOT with high emissions in a modern-ish car.

Not sure why people are suggesting buying new parts, it’s an old car that’s hardly done any miles in the last year, it probably only needs a good high rev drive and make sure it’s warmed up for the retest.

My concern is why the second fast idle results were marginally worse than the first, as by the time you get to a second fast idle test, the engine should of been running at fast idle for a good few minutes. So even if it wasn’t that warm to begin with, things should be improving for the second test.

However, first thing would a good run to get things well warmed up, then straight in for a gas test.

As others have said, give it a decent run, with higher than normal revs, and the occasional push to near the red line in lower gears, to blow out any cobwebs and get the cat nicely warmed up.

A service with new plugs wouldn’t go a miss, but a decent run first is cheaper, provided there are no obvious faults like a misfire, or using more fuel than normal.

Yeah, get it through it’s MOT then slowly get back to the important business of reducing air quality in your neighbourhood.

Nice touch.

If you were a car manufacturer your head would be on a pole by now

Yea because we can all afford a newer car that’s less polluting.

But then that new car takes a lot of energy and resources to make so maybe it’s better given how many miles the op does to keep the old one and not scrap/waste it

Exactly the same as happened to me last year. 16 year old car, short drive to the testing station, failed on emissions with very similar figures, including second fast idle being worse and lambda being OK (which suggests it’s not a sensor). I put in a bottle of Cataclean from Halfords, good run, took it in warm, it passed with less than 50% of the permitted levels. I wouldn’t bother with servicing to get it through the test, only if it needs it anyway based on mileage.

We run an ‘old’ Scenic, W reg year 2000. with 75k on the clock> 45k miles are ours as the 2nd owner.

Its old but not a banger, passes MOT every time. Any service parts are cheap, and easy DIY maintenance.

Get 4 bikes in the back standing upright with front wheels off only.

Why would I need to ever buy another run around? Perfectly good for another few years yet.

Too many cars are scrapped for all the wrong reasons.

As others have said, give it a good run, get the engine hot, then straight into MOT station.

Hey, let us know how you get on.

Yea because we can all afford a newer car that’s less polluting

No

If you live in a built up area, none of us can afford a car that is polluting. None of us

Yet this thread is suggesting that is is acceptable to drive a car that exceeds permitted emission levels. Yes, if it passes the test fine, but by the OP’s admission his mileage is such that emissions will  again exceed permitted levels at some point prior to the next MOT. And it’s unlikely to be the night before.

Ouch, I’m pretty sure a an ancient Toyota has less environmental impact than a modern diesel VAG on a lease that’ll get traded in when it’s 3 yrs old having done 100k.

Not.

I read somewhere  the greenest car manufacturer was Aston Martin as they had the highest percentage of cars still in use vs fuel economy.

How do you think the produce n import a new car?  Magic?

Green party are against scrapping perfectly  servicble cars for new cleaner models as 80 percent of the damage is in the creation of a new one.

Back on to the thread can of Forte fuel treat ment and a small service and go and get it proper hot it’ll be fine.

Yet this thread is suggesting that is is acceptable to drive a car that exceeds permitted emission levels.

No, it really isn’t. It’s a thread suggesting how to fix a car that exceeds permitted emission levels. Wind your neck in and virtue signal somewhere else. Ta.

No, it really isn’t. It’s a thread suggesting how to fix a car that exceeds permitted emission levels. Wind your neck in and virtue signal somewhere else. Ta.

Yes, fix it so it passes the test. which is fine, but at some point based on the OP’s mileage it will fall below the levels allowed. If you think wanting to live in an environment with better air quality is in someway virtue signalling then that is ridiculous. In fact I very much doubt you think that but it would appear based on your comment that you do.

bottle of Cataclean

mmmmmm, yummy – smells so good (as it takes a couple of layers off the mucosa inside your sinuses)

(if it’s that low mileage, maybe use posher petrol or do the cataclean more than once a year, to assuage your guilt and kormoran’s temper)

by the OP’s admission his mileage is such that emissions will  again exceed permitted levels

They do 2,000 miles a year in it.  It’s almost certainly less polluting overall than a modern efficient engine doing 30k+.

kormoran: you sound like a decent bloke but you have no idea about how modern cars work. Emission tests are far fro the be all…

Yet this thread is suggesting that is is acceptable to drive a car that exceeds permitted emission levels.

Actually, most of the advice is to basically get the car up to its ideal operating conditions so that it is assessed fairly, and will probably pass. If it’s still emitting too much crap when it’s at optimum temperature then it will still fail. This is how emissions testing works. Do you think that car manufacturers, when submitting new models for testing, just strap on the apparatus to any old cold car from the cap park on a frosty morning and go straight into the test cycle? Come on now.

Was the oil changed before the test? Low mileage short journey petrol cars of a certain age usually contaminate their oil to the extent that it can push the emissions over the edge – oil change and good long run will bring emissions down.

I would be checking the exhaust doesn’t have any holes in it, this could cause it to fail.

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Yes, fix it so it passes the test. which is fine, but at some point based on the OP’s mileage it will fall below the levels allowed

No, the regulations require it to be tested when the engine is at normal operating temperature. This thread is mostly suggesting that it may have been tested when it wasn’t at normal temperature, and therefore the test is invalid and should be repeated when the car is warmed up properly. My own experience is exactly the same. All cars with internal combustion engines will have higher emissions before they are warmed up; that’s accepted by the regulations – otherwise they wouldn’t have to specify that the engine should be a operating temperature.

Clearly someone to young to remember manual chokes, engines have to run rich when cold.

Yes but the operating temperature can be below the ideal temperature. The test rig won’t let you test a car if it’s below 60 degrees but once at 60 it might not be as good as it is at 80 for the sake of argument. If you get the car nice and warm before the test you give it the best chance to pass.