Cat Converters

[milehighbear]

Is there anyway to tell if your cat converter is good or not. If it isn't, would it be better to buy a new one, or do you think taking a chance on one out of a salvage yard what would odds be that it is bad. Does anyone have one they would want to sell if you know for sure it is good. I have a 93GL. FB71 said when my car didn't pass first time with the HC so high, that very possible that convertor is bad. If i put new one on, what are odds that it would lower HC.

[FestYboy]

odds are good, but with such high HC, i'd think the old cat may have melted a bit. have you pulled it out and inspected the hunnycomb (sp)? seeing that you're not the original owner, ther MAY be a missing component of your cat... that would cause high HC as well. i'd also verify that your O2 is working properly (use a DVOM and watch the voltage swing).

[milehighbear]

I may just take it off the grey ghost and put on the new car and take it over to test just to see if thats it. If it is, then i'd buy a new one.

[FestYboy]

i recomend a visual inspection before swapping, if it's melted and in pieces, don't swap in your spare! the same thing will happen to it.

[eurotiva]

An easy way to check one is un bolt the fromt exhaust and put a shop vac on the tailpipe if it revs up like it has a blockage then your cat is not free flowing.

[FB71]

Euro, he doesn't have a running/clog issue, he failed emissions inspection.

Arty, his HC aren't that high. He blowing about what should be expected with no cat, only 2-3ppm. I suspect the cat is either hollow, contaminated, or just dead. In any case, MHB, replacement should be your primary course.

[milehighbear]

ty guys for input. And thank you FB71, i'm just going to go ahead and get a new one after i get back from Moab, UT in about week. Got a granddaughters wedding to attend plus we are going to camp out for couple days and enjoy country.

[FB71]

ty guys for input. And thank you FB71, i'm just going to go ahead and get a new one after i get back from Moab, UT in about week. Got a granddaughters wedding to attend plus we are going to camp out for couple days and enjoy country.

dang, I'm jealous!!! I skirted Moab when I rode my motorcycle cross-country in '05. What I saw of Utah was stunning!!!

[milehighbear]

I'll take a few pictures just for you Jim

[FB71]

AWESOME!!! Thanks!!!

[graywolf_14]

Ok sorry to jack but I have a question about cats. My neighbor took his cat off his fest and gutted it and ever since it doesnt run right. He said it seems to have no power and sputters now. Which I did this to my fest with no problem though.

[TominMO]

cat

Very strange! It should run better if it was clogged, and the same if it wasn't. I'd check to make sure the exhaust is all hooked up; then look for other unrelated issues; i.e. did he do any other mods when he did this? Changed timing belt for example, but it's a tooth off?

All poor-running issues boil down to four factors:
air
fuel
spark
timing (either valve timing or ignition timing)
One (or more) of 'em's not right.

[graywolf_14]

Yeah that is what I was thinking but I dont know. I havent talked to the guy personally my dad was trying to buy the car from him for me. And my dad told the guy about my love for the cars and the guy asked him about it.

[Pocket_Rocket]

Is there anyway to tell if your cat converter is good or not. If it isn't, would it be better to buy a new one, or do you think taking a chance on one out of a salvage yard what would odds be that it is bad. Does anyone have one they would want to sell if you know for sure it is good. I have a 93GL. FB71 said when my car didn't pass first time with the HC so high, that very possible that convertor is bad. If i put new one on, what are odds that it would lower HC.

I don't know about the laws where you live, but where I'm from, junkyards aren't allowed to sell used cats; it's illegal. If your cat is bad, you have to replace it with a new one. Also, most of the shops where I've check won't install a used cat on your car...

[drof 89]

I don't know about the laws where you live, but where I'm from, junkyards aren't allowed to sell used cats; it's illegal. If your cat is bad, you have to replace it with a new one. Also, most of the shops where I've check won't install a used cat on your car...

This is true in Pa. too. Unless the law has changed. Had a guy sell me on for the Subaru turbo out of a big yard that was like new for $20.00. He wrote it up as a tail pipe. Saved me a big pile of money!