MK5 Golf GTI
All Things Mk5 => Mk5 General Area => Topic started by: jedi-knight83 on September 08, 2012, 12:18:32 pm
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Well... I say failed... Technically it failed but its all about WHO you know :ashamed:
Anyway... I thought the pre cat delete didnt affect emissions?
I dont have the actual figure but I was told the lambda reading wasn't within tolerance for the MOT?
Anyone else had this issue?
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Had my mot done last week, and with my pre cat out I had the same issue as you, but as you say it is who you know!! ;-)
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I thought the pre-cat only affected cold emissions, and that it was only necessary in Germany?
My BlueFlame (obviously without pre-cat) passed it's MOT at an Audi main dealer only last month
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Mine sailed through the MOT with the pre-cat removed :happy2: (at a VW dealer).
I did take it for a thrash down the bypass before the MOT to get it hot. The pre-cat aids cold start emissions so if the car is hot when it's MOT'd it should be fine.
Sounds like your normal CAT may be at fault :sad1:
Gray
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Mine sailed through the MOT with the pre-cat removed :happy2: (at a VW dealer).
I did take it for a thrash down the bypass before the MOT to get it hot. The pre-cat aids cold start emissions so if the car is hot when it's MOT'd it should be fine.
Sounds like your normal CAT may be at fault :sad1:
Gray
Sounds like a good excuse to upgrade my downpipe and cat then :)
IS there anyway to check the main cat?
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If it makes a difference... i'd not used the car for about 6 days prior to the MOT and it was a very short drive through town to the garage. I dont know how hot they then got it?
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I have no precat and running a high flow Miltek cat and emissions were well in spec. Must be yoyr normal cat faulty.
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Sounds like they did the MOT without preheating the cat...
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i might take it for a blast and then pop it in next week for them to recheck emissions when its hot.
If it still fails I will look at getting a miltek downpipe and sports cat.
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If it failed on lambda readings then it's not the precat at fault, it's either running too rich or lean. If it filed on hydrocarbons or CO then it could be blamed on the precast removal.
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If it failed on lambda readings then it's not the precat at fault, it's either running too rich or lean. If it filed on hydrocarbons or CO then it could be blamed on the precast removal.
Hmm.. I'll message R-Tech then. Annoying if it needs adjusting as its running beautifully at the moment.
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I have passed 2 mot's with precat removed at two different garages one being kick fit and it passed with no issues.
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Hi,
Sorry to High-Jack
What the performance advantages of removing the pre-cat, also does anyone know if this can be removed from the R32 !
Cheers Peeps.
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I always take my car for a long drive before the MOT to heat up the cat and the brakes etc to make sure it passes easily. My car passed with the precat delete this year and passed with ease.
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as PDT said above.... seems my issue may not be cat related at all but fuelling related.
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the engine must be at running temp to do the test, taking it for a thrash before the test will get the cat nice and hot and burn off any crap, without the thrash the cat will still be nice and hot, as above sounds more like a cat issue but without seeing the figures from the test it could be a cat, lambda sensor fault
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It's unlikely to be the map at fault, an MOT emission test is not carried out with the engine under load. Typically the areas in a map that are altered for performance gains are nowhere near the areas the ecu will look up during emission testing.
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My PPM's on mine with the Miltek was around 40 ppm. The limit here in Ireland is 200ppm.
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If it failed on lambda readings then it's not the precat at fault, it's either running too rich or lean. If it filed on hydrocarbons or CO then it could be blamed on the precast removal.
Hmm.. I'll message R-Tech then. Annoying if it needs adjusting as its running beautifully at the moment.
Mine is R-Tech mapped too. However as PDT said, it's unlikely to be the map