DD Catalytic Converter Question

[pajeff02]

Since selling my Ranger, I have been driving our '98 Dodge Durango on a daily basis. Quite regularly, it will trip the Check Engine light for a "catalytic inefficiency" code. It is the same code every time. It has the 5.2 with a 2 into 1 exhaust setup, so there is only one (1) converter and one (1) rear O2 sender. I just turned 96,000 miles on it this week.

I have not noticed any driveability issues, the power seems the same as it always has, and the mileage has not suffered at all (not that it ever got decent mileage to begin with). I hate throwing parts at something and am unsure if I have a faulty O2 sender, an actual bad converter, or if it is just the crap they sell for gas around here that is causing the light.

[Smittro]

318? My guess it's not much different than how our cars emissions systems work.. Most likely the cat is crapping out.. I don't follow Dodgit's much so I can't tell you which of the 2 is the lesser of 2 evils as far a price.. But I'd start pricing both imho.. Can't see a cat delete harming anything either.. I have a buddy whom had an old mid or late 90's duhkoduh (318), had his whole exhaust fall off he replaced it lol by piecing it together without a cat.. Still ran fine for a dodgit.. However fine for him and fine for you maybe 2 different things lol.. It did'nt seem to misfire or have any AFR issues to me Hope that helps..

[pajeff02]

I really don't have a problem with a "test pipe", but can I get an O2 sim for this thing? Check Engine lights kind of bother me.

[Smittro]

I really don't have a problem with a "test pipe", but can I get an O2 sim for this thing? Check Engine lights kind of bother me.

Y'd imagine yes, tho I also can't see those sims being anymore reliable than they are for us.. In many cases they work for only a short time and sometimes not @ all.. Kinda hit or miss it seems.. Let me take a look here..

[Cutlass]

I made a mechanical O2 simulator for my Blazer with a hollowed converter and it worked great. Go to the parts store and buy 2 Help!brand spark plug anti-foulers.


Drill out the one to make room for the sensor and then screw them together like this:


This spaces the O2 sensor away from direct exhaust flow which makes the sensor read lazy because it only sampling a small amount of exhaust and simulates a fully functional converter.

It works!!! I've tried it.

[Smittro]

With a quick search, it looks like a place called, "Speedtweaks" carries what's called a "Kat box" and which goes between the harness plug for it.. I also see they may have changed the name to "02 SIMM".. Quote I read was ~80 bucks..

[pajeff02]

Now that is a great idea!

What about the fact that I don't seem to have any failing converter symptoms?

[Smittro]

I made a mechanical O2 simulator for my Blazer with a hollowed converter and it worked great. Go to the parts store and buy 2 Help!brand spark plug anti-foulers.


Screw drill out the one to make room for the sensor and then screw them together like this:


This spaces the O2 sensor away from direct exhaust flow which makes the sensor read lazy because it only sampling a small amount of exhaust and simulates a fully functional converter.

It works!!! I've tried it.

WOW! I did'nt know you could do that! I've thought about trying something like this before but never did.. Thanks Cutlass! I'm gonna give this a try myself too..

[Cutlass]

Now that is a great idea!

What about the fact that I don't seem to have any failing converter symptoms?

normal. I see the codes for bad converters far more often then the symptoms of a bad converter

[Smittro]

Now that is a great idea!

What about the fact that I don't seem to have any failing converter symptoms?

Mine did'nt either then one day BOOM I figured it had to have been going for some time.. I swear I thought the motor popped.. I have a thread here about the experiance.. I mean it ran way bad.. Popped, back fired, missed, just sounded awefull.. But the day before she ran just fine.. Good Luck..

[pajeff02]

Just did a little on-line looking and found that converters aren't all that expensive. May just slap one on it and see what happens then. I always thought I would be getting some symptoms if it was failing. Thanks for the info guys!

[TerribleTed]

Since selling my Ranger, I have been driving our '98 Dodge Durango on a daily basis. Quite regularly, it will trip the Check Engine light for a "catalytic inefficiency" code. It is the same code every time. It has the 5.2 with a 2 into 1 exhaust setup, so there is only one (1) converter and one (1) rear O2 sender. I just turned 96,000 miles on it this week.

I have not noticed any driveability issues, the power seems the same as it always has, and the mileage has not suffered at all (not that it ever got decent mileage to begin with). I hate throwing parts at something and am unsure if I have a faulty O2 sender, an actual bad converter, or if it is just the crap they sell for gas around here that is causing the light.

> its a bad cat or a cat that is on the edge....
>get a cheap smog test done. The numbers will show if the cat is good or bad.
>remember that there is an O2 sensor before the cat and sometimes one after the cat. The one before measures AFR and if your car seems to be driving fine-and you get a cat effic. code-then its most likly the cat.

Smog test it to fnd out,,or replace cat and rear o1 sensor. Also,,,if it passes smog,,take it to a tuner and get all post cat codes deleted,,or better off,,buy a checvy camaro or vette,,etc,,,dump the dodge,,ha ha,,

[pajeff02]

We live in an area of the state that does not require smog testing. As such, none of our local service stations have the equipment. Possibly the dealerships, but I have several friends that work at them and they have never mentioned smog testing a car before.

[pajeff02]

Just picked up a new cat from the Zone for around $80.00 -- made in U.S.A., 5 year warranty and even came with a cool Cherry Bomb sticker.