Car emissions check

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Just a quick question.

Outside of actually getting a MOT. Has anyone, or does anyone know if its possible to turn up to a garage/test center with a car that currently has a valid MOT. And ask them to check the emissions of the car without actually having a MOT carried out? therefore if it fails you wont fail a MOT?
 
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Basically i have a heavily modified car. Usually i put it back to standard - remove supercharger, standard injectors, standard ECU, standard airbox standard catalyser. It probably takes nearly a full day to take it all off and put it back on again.

I am wanting to put the standard cat on ONLY and see how it fairs on the MOT emissions so i can see if i can get away with just placing the standard cat back on and leaving the rest off without risking failing the MOT which is due in december.
 
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had a renault checked last year just rang the mot station i use and asked for a emmision test they carried it out no problem, didnt effect the mot and it failed by the way . so at least i could rectify the problem.
 
Soldato
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Basically i have a heavily modified car. Usually i put it back to standard - remove supercharger, standard injectors, standard ECU, standard airbox standard catalyser. It probably takes nearly a full day to take it all off and put it back on again.

I am wanting to put the standard cat on ONLY and see how it fairs on the MOT emissions so i can see if i can get away with just placing the standard cat back on and leaving the rest off without risking failing the MOT which is due in december.

If you don't actually care about poisoning people just find a garage that will fudge the numbers for you. About as ethical.
 
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If you don't actually care about poisoning people just find a garage that will fudge the numbers for you. About as ethical.

people get poisoned enough by airplanes(which i dont use) diesel cars, buss's, trucks old cars that dont require a cat or an MOT, bonfires, stoves etc to believe me driving my car <1500 miles a year is not going to lead to anyone getting Ill due to my actions
 
Associate
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Basically i have a heavily modified car. Usually i put it back to standard - remove supercharger, standard injectors, standard ECU, standard airbox standard catalyser. It probably takes nearly a full day to take it all off and put it back on again.

I am wanting to put the standard cat on ONLY and see how it fairs on the MOT emissions so i can see if i can get away with just placing the standard cat back on and leaving the rest off without risking failing the MOT which is due in december.

If your tune is good then it should pass with a standard cat. The test is not done under load, its idle and RPM held at about 2500RPM.

What car is it?
 
Soldato
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If you don't actually care about poisoning people just find a garage that will fudge the numbers for you. About as ethical.

Depends how you look at it, if it's a weekend toy & only does 1k a year it's likely irrelevant in the grand scheme of things as will still chuck out less emissions in a year than your average eco shoe box.

Regarding emissions tests, i had one done to help me diagnose an overfuel issue, it cost me a fiver.
 
Man of Honour
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Regarding emissions tests, i had one done to help me diagnose an overfuel issue, it cost me a fiver.

Around here they will bill you for their time - depending on garage either minimum 15 minutes or minimum 30 minutes. But the ones I regularly use would be happy enough to do an emission test. (So £10-75 depending on which garage).

If you don't actually care about poisoning people just find a garage that will fudge the numbers for you. About as ethical.

Since the IIRC May 2018 changes there are a lot less places that will fudge an MOT as there is more accountability now.
 
Soldato
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Poisoning people....lol. If it was a dirty sooty diesel then fair enough.

It's not just about spot, but if that's how you justify it then ok.

If it's just a track day car then sure but otherwise every person you are driving past you are exposing them to much greater harmful emissions.
 
Soldato
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I had an emissions test on mine after some mods, it passed fine, then at the same place for the MOT it failed. Returned to stock cat to re-do MOT to pass. Ran a few more tests later with the mods and it seemed to yoyo between passing and failing which we've not figured out why. I do have a brand new one to test again to see if the current cat is faulty or if it isn't good enough to get it through. Garage I used only charged once for the test for time.
 
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I had an emissions test on mine after some mods, it passed fine, then at the same place for the MOT it failed. Returned to stock cat to re-do MOT to pass. Ran a few more tests later with the mods and it seemed to yoyo between passing and failing which we've not figured out why. I do have a brand new one to test again to see if the current cat is faulty or if it isn't good enough to get it through. Garage I used only charged once for the test for time.

Probably just wasn't quite hot enough on the runs it failed.
 
Soldato
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If the car had 2 cats and one was removed (common when tuning), it can just push it over the edge if you then fit a sports cat, or if testing when cold. That happens on the gt86.

One trick is adding a fuel additive before the MOT ;)
 
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