Can I pass emissions without first cat?
- Thread starter Zagato
- Start date
You will struggle to pass or wont even pass without the first cat as that one does most of the work as the second one doesnt get hot enough. A few people have had problems. Noddie being a recent one.
You can just swap the standard manifold and cat come MOT time and swap again when its passes.
You can just swap the standard manifold and cat come MOT time and swap again when its passes.
Where it is located is probably the best location for it heat wise. Alot of people remove the 2nd cat and just replace it with a straight through pipe. But putting both next to each other is a bit pointless. It would be alot easier to just swap manifolds when the times comes.
baguete
Site Supporter
I think that CAT's only work with high temperature, thats why is best to "trash" to car before you go to a MOT, so the CAT is hot enough to filter all the crappy gases...
Shaun
***StaGGeRed***
However your car might have to wait a while until being MOT'd so sometimes this won't work
baguete
Site Supporter
However your car might have to wait a while until being MOT'd so sometimes this won't work
Dont know how its done in UK, but in Portugal the test is done at 3-4000rpm, so the CAT gets hot enough...
Shaun
***StaGGeRed***
there are 2 parts of the test over here,
idle. and fast idle like you said around 3k iirc?
still can fail though with both cats so everyone needs to sort it out before heading off to the mot. you can buy testers off of eBay etc.
i have one in the garage. (gas tester)
baguete
Site Supporter
Yes, something around 3.000rpm.
Buy a gas tester? Nah, i prefer to buy a MOT, the car passes for sure... :laugh:
sleeper_ss
Ex. Club Member
It can also help to take the car for a good thrash before the test to clear out some of the deposits collected in the exhaust system,especially if the car has been pottered around town in by an 80 year old nun.
