How Many Cats
- Thread starter Joreysdad
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Can anyone tell me how many cats my 1999 ML430 has please, specifically interested to know if she has a pre cat. It's all about decat now she's lpg and keeping the right side of the MOT man
http://www.detali.ru/cat/oem_mb2.as...GA=722.663&CT=F&cat=04S&SID=49&SGR=030&SGN=01
The petrol one has two pre cats
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Joreysdad
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mmmm
So - does 1 pre cat count for mot, as in it is present and working (although I am sure LPG will take care of emissions issues so it's only there for the legal requirement) if I have the other ones removed? Any advice on what to take out and leave in is appreciated
One cat (main) is knackered and i see no point in spending 900+ to replace (I know I can put on cheaper cats but I don't like to put non mercedes bits on my cars)
So - does 1 pre cat count for mot, as in it is present and working (although I am sure LPG will take care of emissions issues so it's only there for the legal requirement) if I have the other ones removed? Any advice on what to take out and leave in is appreciated
One cat (main) is knackered and i see no point in spending 900+ to replace (I know I can put on cheaper cats but I don't like to put non mercedes bits on my cars)
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television
Always remembered RIP
- Joined
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- Your Mercedes
- 2002 SL500, 216 CL500, all fully loaded
Canada on Ebay
television
Always remembered RIP
- Joined
- Mar 14, 2005
- Messages
- 164,073
- Reaction score
- 377
- Age
- 89
- Location
- Daventry
- Your Mercedes
- 2002 SL500, 216 CL500, all fully loaded
So - does 1 pre cat count for mot, as in it is present and working (although I am sure LPG will take care of emissions issues so it's only there for the legal requirement) if I have the other ones removed? Any advice on what to take out and leave in is appreciated
One cat (main) is knackered and i see no point in spending 900+ to replace (I know I can put on cheaper cats but I don't like to put non mercedes bits on my cars)
Many threads have shown that by cutting open and removing the bottom cats has not stopped the car from getting a MOT. I sliced mine open, removed the ceramic insert and welded shut, just as others have done. This was done to over come a rattle where the CAT was loose. What was wrong with yours
I took them out of my old SL320 and it passed, the upper CATs rarely fail
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Joreysdad
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Malcolm the bottom cat rattles, which lots do with no major probs, but I'm also having problems on startup with petrol. The LPG system requires the engine to reach 40 degrees c before switching over which it does quite quickly but in the meantime problems on petrol occur. The LPG system is McClaren developed and not likely cause of problems as it is designed for mercedes.
MAF and O2 sensors have been replaced but I think that damage has been done to cat because problems with MAf and sensors were not noticed and addressed quickly enough by previous owners.
Now when i start her up on petrol b4 she switches over to lpg she runs a little rough and when you floor her on lpg or petrol you can feel a little hesitation and possible missfire at higher revs. Chats with specialist and reading up lead me to believe cat cause of issues. I know I can take them out emissions wise but looking for MOT friendly option. Want to leave a cat in to cover legal requirement, but take the main ones out to boost power, fuel consumption and sort the issues with smooth running.
However I'm not sure that if i leave the pre cats in I'll get the power boost and fuel consumption benefits I expect - don't know whether to take them all out and put a cat back in for mot?
I'm sure someone here has the answer
MAF and O2 sensors have been replaced but I think that damage has been done to cat because problems with MAf and sensors were not noticed and addressed quickly enough by previous owners.
Now when i start her up on petrol b4 she switches over to lpg she runs a little rough and when you floor her on lpg or petrol you can feel a little hesitation and possible missfire at higher revs. Chats with specialist and reading up lead me to believe cat cause of issues. I know I can take them out emissions wise but looking for MOT friendly option. Want to leave a cat in to cover legal requirement, but take the main ones out to boost power, fuel consumption and sort the issues with smooth running.
However I'm not sure that if i leave the pre cats in I'll get the power boost and fuel consumption benefits I expect - don't know whether to take them all out and put a cat back in for mot?
I'm sure someone here has the answer
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