Has anyone had a good luck using an universal cat welded in place of original post-cat? I failed on local smog test (Europe) and due to high CO and HC numbers I was told that it must be the converter not working at all or guted out. I don't hear any rattle though.

If uni-cat was used, did you gut out the pre-cat?

 

A possibility exists that one or more of your oxygen sensors are out of whack but not throwing a code.

 

Their statement was that it's running too rich. I replaced a really corroded distributor cap and rotor hoping to improve the situation, spark plugs and wires were new already. Still no luck.

And yes, I'm not getting any code, the basic diagnostics is clear.

I've noticed that the right O2S was contaminated with oil drips a little but it looks like it ticks well. However I cannot say if that values are correct.

 

O2 sensors can get "lazy" over time and not read/report correctly while not throwing codes.

Your cats might might clogged sufficiently to affect their function too.

If there are prior owners, maybe someone drilled out the cat?

So many things might be wrong. Distributor could be off a gear.

Maybe a basic tune up is needed first?

 

Forgot to add, these engines work best with oem plugs and ignition parts.

 

I'm 4th owner or so. The previous owner "passed" smog test and inspection but it looks very suspicious, don't ask me how did he proceed

I'm probably going to weld in an universal cat and use new O2S for sure. This is 2001 with latest distributor model. I'd say it's placed correctly. The truck doesn't run bad, it has 160k miles. However I don't have a comparison with other truck to see the difference. They are kinda rare here in Czech.

Also the head gasket was blown and that was solved by one of previous owners. Could it be possible that the water leak into cylinders destroyed the cat(s)?

 

Funny, it turned out that I have a different implementation than the US versions have. I don't have any pre-cat, only the main cat. I will make some diagnosis to see if it actually works and then decide to replace it.
http://1drv.ms/1WBMdzx

EDIT: Now I realized that I have 99 model year and not 2001 as I thought. So now RockAuto lists the correct cat that should I use and it's only single.

 

most of those cheap cats only seem to last a few years at best. last job i worked at they started coming back after the 2nd or 3rd year i was there due to the p0420 code coming back so we would just swap a new one in there. no one wants to buy the expensive ones from the dealer. im so glad i dont have to deal with emissions anymore i dont think any of my trucks would pass

 

Do you mean the universal ones or the Walker brand I listed above (factory fit)? The Walker is really not that expensive. I think I will pick that one later on.

 

the walkers fall under the cheap category. maybe you will get lucky but it seems like under most circumstances they only last around 2 years