Bad cat question.

[02gcaravan]

If a TD has been driven for a while with a bad O2 sensor, running "pig" rich, would the smell need to be driven out of the cat or would it be apparent after only a few minutes?

Before I had the sensor replaced the exhaust smell was a raw gas smell, "almost". I just got the O2 installed today and I have driven it for maybe 4-5 miles, of that 2-3 was city stop and go and the rest was a 65 - 70 mph with a WOT run getting on the highway. The fuel/exhaust smell is still there but MUCH less than it was before, almost to a regular exhaust smell.

Thanks!

[jdawg]

If you have a plugged cat it is REALLY hurting your performance and possibly being clogged, you may have an exhaust leak before the cat. I would check it out and replace the cat.

[turbovanman]

If your exhaust stinks, its not the cat, your running too rich. You need a shop to do a sniffer test and check out your fuel system.

[86lance]

also the cat may be completely ruined now that its had nearly raw fuel running thru it for a while. Good way to check is see if the exhaust pipe is hotter after the cat then it is vefore it entered it. you need one of those little laser thermometers though.

[turbovanman]

Quote:

Originally Posted by 86lance also the cat may be completely ruined now that its had nearly raw fuel running thru it for a while. Good way to check is see if the exhaust pipe is hotter after the cat then it is vefore it entered it. you need one of those little laser thermometers though.

Checking temp doesn't work. I have checked brand new ones and have had the same temp going in and going out. The best and really, the only way is a sniffer. You check the readings before the check, then after the cat and compare.

[02gcaravan]

Would an E-Check give me some answers? I have 30 days to get one before my temp tag runs out.

Right now, after driving to work, it's smelling ALOT better than it did Friday. Actually it's smelling alot like my Saturns use to - "sort of rich". LOL!

I don't think the cat is plugged - the 600 is performing quite well now. I just a miss at idle in gear and in park. I'm going to be replacing some of the vaccum lines on Sunday so I'm hoping that will help with the idle.

BTW: Should a TD smell sort of rich from the exhaust?

[turbovanman]

The only time is should smell rich is under boost or at WOT.

[02gcaravan]

Quote:

Originally Posted by turbovanman The only time is should smell rich is under boost or at WOT.

On my Saturns, at idle in park, I could smell the "slightly rich" exhaust smell. It wasn't too much, just enough to let you know the car was running. That's what I was smelling today - just a hint of richness. Come Sunday I'll have a much better grasp of what's going on in the fuel dept. I'm installing a WBo2 ( and a boost gauge ). I'll have numbers to post up IF the problem(s) are still there.

If I don't have any more problems before Sunday I'll post up my readings Sunday night / Monday afternoon to see if the 600 is running the way it should.

Thanks!

**EDIT** For future reference: What should my A/F ratio be at idle on a warmed up car? 1985 Dodge 600. T1 A-413, completely stock, so far. Oh, I do have a K&N "drop in" filter, that's it.

[turbovanman]

Idle and no boost, you should be seeing around 14.7:1 with the engine warmed up. Boost and WOT, not sure exactly but from 14:7 to 12:1.

Saturn is not a good one to use, there engines are horribly inefficient and burn oil. I do lots of repairs on those and they fail our emissions tests alot. They need a good cat to pass,

[02gcaravan]

Quote:

Originally Posted by turbovanman Idle and no boost, you should be seeing around 14.7:1 with the engine warmed up. Boost and WOT, not sure exactly but from 14:7 to 12:1. Saturn is not a good one to use, there engines are horribly inefficient and burn oil. I do lots of repairs on those and they fail our emissions tests alot. They need a good cat to pass,

The oil burning issue I knew about but the inefficientcy I didn't. I do know that the stock engine and internals are good for about 220 whp with fuel managment.

If my cat is indeed bad that's alright. I just hope it lasts until I upgrade the exhaust. If I fail the E-Check then I'll know when I'm upgrading I'll also be checking out the wires before then as well, just standard practice on a used car. I did those and plugs on my other two cars when I bought them. Doesn't hurt anything but the wallet

Speaking of the E-Check: If I do fail, is there anything that the E-Check "checks" that is strictly cat related? Or is everything out the tailpipe cat related?

[turbovanman]

Quote:

Originally Posted by 02gcaravan Speaking of the E-Check: If I do fail, is there anything that the E-Check "checks" that is strictly cat related? Or is everything out the tailpipe cat related?

If the ox is good, no fuel issues, IE bad reg, then the cat finishes up. You can still have a good cat and fail if its too rich, misfiring, etc.

[mech1nxh]

http://*****************/forums/showthread.php?t=1395
this thread will help with the emissions questions.....enjoy!!!

mech1nxh

[mech1nxh]

Quote:

Originally Posted by mech1nxh http://*****************/forums/showthread.php?t=1395 this thread will help with the emissions questions.....enjoy!!! mech1nxh

sorry for the double post, I needed to add a p.s.......and exceeded my time limit

feel free to p.m. me for emissions help, I would be more than glad to lend
assistance