Removing Catalytic Converters MOT Implications

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Rargh
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Removing Catalytic Converters MOT Implications

#1 Post by Rargh » Thu Jul 04, 2013 11:21 am

Hiya

I need to get a front pipe replaced and it will be a bespoke job (as the dealer wants £1100 for the part and its not available anywhere else :shock: ) the guys in the shop noticed that I was running LPG and said that if I wanted they could remove the cats and replace with straight pipe. They said they could do this as cats are not required for an MOT on a car running lpg.

Now my question is this worth while? They said there would be a small performance increase and increased MPG.
Is it true about the removal of the cats do not effect the MOT? My car is not LPG on the logbook but I have informed the insurance company.

Car is: 2001 Audi A4 Avant Quattro 2.8.

Thanks in advance

Gilbertd
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Re: Removing Catalytic Converters MOT Implications

#2 Post by Gilbertd » Thu Jul 04, 2013 3:07 pm

Since January last year a car that was originally fitted with cats must have them fitted at MoT time or it is an automatic fail. Even though if presented for test running on LPG and is tested on LPG it doesn't actually need them. However, if you have pipes that look like cats so it appears to have them fitted, then how does the MoT tester know if there is anything inside them ;)
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

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mat_fenwick
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Re: Removing Catalytic Converters MOT Implications

#3 Post by mat_fenwick » Thu Jul 04, 2013 5:01 pm

I can personally vouch for the fact a well set up LPG system will pass the MOT emissions test without a cat fitted, as I was doing that a few years ago - must admit I was nervous the first time I took it for a test minus cats though!
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classicswede
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Re: Removing Catalytic Converters MOT Implications

#4 Post by classicswede » Fri Jul 05, 2013 1:17 am

To pass the MOT you will need cat casings fitting so it looks like it still has a cat
http://www.classicswede.com/
http://www.classicswede.co.uk/LPG/cat17 ... 10800.aspx

LPG installer Anglesey North Wales

DIY LPG Kits

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Rargh
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Re: Removing Catalytic Converters MOT Implications

#5 Post by Rargh » Fri Jul 05, 2013 8:02 am

Thanks for all the good info guys. Looks like it will be worth leaving the cats in just to avoid hassle.

Cheers

mat_fenwick
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Re: Removing Catalytic Converters MOT Implications

#6 Post by mat_fenwick » Fri Jul 05, 2013 9:44 am

I should clarify I wasn't disagreeing with Gilbertd (as it appears now when re-reading) - just stating that functionally they are not required. Although at the time there was no visual check on the MOT that they were fitted, as there is now.
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Gilbertd
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Re: Removing Catalytic Converters MOT Implications

#7 Post by Gilbertd » Fri Jul 05, 2013 10:43 am

I didn't read it as you disagreeing and enough people have in the past so it wouldn't bother me anyway. Where's your signature then Mat?
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

Proud to be a member of the YCHJCYA2PDTHFH club.

mat_fenwick
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Re: Removing Catalytic Converters MOT Implications

#8 Post by mat_fenwick » Fri Jul 05, 2013 11:21 am

I hadn't bothered mentioning it here seeing as you're already a member, but maybe there will be some interest in membership on the other forums I use.
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Gilbertd
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Re: Removing Catalytic Converters MOT Implications

#9 Post by Gilbertd » Fri Jul 05, 2013 11:27 am

There's always curiosity and the more members the better......
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

Proud to be a member of the YCHJCYA2PDTHFH club.

bootlegbob
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Re: Removing Catalytic Converters MOT Implications

#10 Post by bootlegbob » Sun Jul 07, 2013 8:44 pm

Interesting topic .
My cat is knackered so it's no use but as I have a factory fit LPG and never run on petrol it flys thru the MOT .
The only problem I can see is if anyone can work around the 02 sensor problem .
I have the engine management light on all the time as I get a fault reading from the second 02 sensor .
While this doesn't bother me my friend at the mot station tells me that every year they tighten things up and anytime soon if the EM light is on it will be an mot failure

Gilbertd
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Re: Removing Catalytic Converters MOT Implications

#11 Post by Gilbertd » Sun Jul 07, 2013 9:49 pm

Replace it with a couple of resistors configured as a potential divider to feed the correct voltage to the ECU?
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

Proud to be a member of the YCHJCYA2PDTHFH club.

classicswede
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Re: Removing Catalytic Converters MOT Implications

#12 Post by classicswede » Sun Jul 07, 2013 10:45 pm

Some cars can be cured by just cutting the signal wire.
http://www.classicswede.com/
http://www.classicswede.co.uk/LPG/cat17 ... 10800.aspx

LPG installer Anglesey North Wales

DIY LPG Kits

07824887160

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