New Catalytic Converters

[grain2glass]

Hello,
I have been looking into buying an fzj80 for the last 3 months or so. I have had some close calls, but nothing has landed yet. My newest target seems alright, with the following exception. The ad states, "This truck will not pass emissions as it sits, it needs cats and then would pass." I haven't gone to see it yet, but one of my buddies is going to take a look in the next few days. I'd rather not quote prices, but it seems reasonable to replace both cats. My question to the forum is, what other things would indicate an exhaust/emissions problem beyond just cats? That is, are there any ways to tell I'll need to do some other work besides bolting on the cats to pass emissions? What should I ask my buddy to look at specifically? Will driving without the cats cause damage to the vehicle? I should have undercarriage photos after my buddy checks it out. Thanks in advance for any guidance to a would be fzj80 maniac and feel free to point out my obvious ignorance on the subject.
Cheers,
Eli

 

[Koffer]

It could be tossing a PO402 Cat efficiency code which can be caused by leaks before the O2 sensors and if 95 to 97 between the 2 at the gaskets . It can also be old o2 sensors as most have dealt with this (they do get worn out and slugglsh ) and replacing them with new OEM units and checking for leaks has cleared up the problem.
The only reason I had to replace my cats were there was more air then metal left from rust .

 

[grain2glass]

Thanks for the reply, Koffer. It is a 96. So checking for rust on the entire exhaust system would be a big indication of problems beyond the cats. Since it's a 96, that means it's OBDII, so I can borrow a scanner from an auto parts store to figure out the code, correct? If the cats are off, then a CEL light should show, right?

 

[nuclearlemon]

measure temps going into the cats and coming out. should be about100 degree difference.

 

[Koffer]

Thanks for the reply, Koffer. It is a 96. So checking for rust on the entire exhaust system would be a big indication of problems beyond the cats. Since it's a 96, that means it's OBDII, so I can borrow a scanner from an auto parts store to figure out the code, correct? If the cats are off, then a CEL light should show, right?

If the cats are cut off , the light will most likely be on. A code reader will allow you to pull codes and get an idea of what is going on .

Good luck with it

 

[CJF]

Living where a rig must pass emissions before being registered, no WAY would I buy a rig that won't currently pass (unless the price was HUGELY discounted). There're just too many things that could be causing the problem, and no way to tell how much time/money it will take to fix it.

Plus, his claim that the cat's are the problem is almost guaranteed to just be a wild-ass guess.