Catalytic Converter: Confused

[bav401]

First off, hello everyone and thanks for future replies.

Okay so I tried searching for answers about the 4 catalytic converters on my 00' 4.0 ex, now I am even more confused than before I started.

My question's are...
1) Why 4 converters?
2) Do I need all 4?
3) I just added dual exhaust, not true dual's(single muffler), and it is no where near has loud has i want it to be. Is it because I have 4 cats?
4) How many can remove without throwing a check eng. light?
5) Should I just cut all 4 off and add one hi-flow cat?

Thanks again.
One more thing to mention. Not worried about emission check.

 

[fordpower1989]

i have a 99 wit 4 also and in CO we need two to pass emissions. u should check the division of transportation regulations on catalytic converters. i hate the four converters cause it takes away power if u do a new exhaust u will feel a good diff in power too.

edit i jus read the part about ur not worried about emissions, then cutting four off and puttin one in should not be a problem it will give u a good amount of power it should help out the sound too

or if u want jus straight pipe it to the muffler..

 

[bav401]

Thanks for the suggestion. Do you know if it will kill my O2 sensor(s) or throw a check engine light? I cannot find a clear answer on that for either cutting two cats off, cutting all 4 cats and adding a hi-flo, or straight pipe. That would be an expensive opps.

 

[Dan Whitaker]

It is a federal violation to remove any catylitic converter.

Don't be surprised if this thread gets deleted.

 

[Maniak]

Removing the Cats isn't a good idea, not to mention illegal.. Your tuck is odb-II and it checks to make sure the cats are working..

I you remove them and replace them with high flow cats (so you can have 2 instead of 4) that work well enough to replace your orig ones the O2 sensors should register they are working and not throw a code.

You also then have to worry about your local inspections.. For example, in Ca. You need to keep the same # of cats, in the factory locations and can only replace them if damanged/not working.

In Az (at least Pima County) you need to have the cat, but you can replace it with a high flow universal and our was moved 6" back.

~Mark

 

[matemorh]

If it help..... I remove the 3 cat on my 99 cougar and without MILS the check engine light came on!!! Not one single issues with MILS!!!

 

[xtbt]

Same truck as thread starter ...

I'm in the same situation as bav401, my truck has 4 catalytic converters, the first 2 are smaller than the last 2. One of the smaller ones is not even reachable without taking a lot of other engine parts.

I live in Mexico, so here's no smog check, but I'm very concerned about contamination, so even if all my neighbors take off their cat converters I'm looking for a good less-contaminant-more-truck-power solution.

The emission path goes like this:

1.- 1 cat on each one of the exhaust start. So there are 2 before the Y.
2.- 1 right after the Y.
3.- 1 right after the one that's right after the Y.
4.- O2 sensor right after the last one.

I've not seen any other O2 sensors on the exhaust line so I think that's it.

Can I replace all 4 stock cats with only one High-Flow cat just before the O2 sensor without throwing any code to the computer ? Like I said before, in my country there is no smog checks but I don't want to remove all the cats, I want to have at least one if that's enough for the O2 sensor.

Thanks in advance.

 

[hazmat456]

you should be able to remove the rearmost two on a 5.0 on anything else you can only delete what is after the last o2 sensor.state laws are all different so watch yourself

 

[xtbt]

you should be able to remove the rearmost two on a 5.0 on anything else you can only delete what is after the last o2 sensor.state laws are all different so watch yourself

I think I'm not really clear. I'm gonna take some pictures tomorrow morning and post them in here so you can watch hows the exhaust line. Maybe someone can help me with some ideas.

Anyway, I'm gonna do the exhaust modification on the first days of November.

Thanks in advance.