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ScottD
11-13-2008, 12:36 PM
My 90 Dakota Sport passed emissions 2 years ago with 193k on it and the ORIGINAL cat.

Now, after putting on Edelbrock headers, a new EGR valve, new 02 sensor, a 180 degree t-stat, and a Catco cat, it has failed twice. The plugs, wires, cap and rotor all have under 10k on them.

Thoughts? Is the Catco cat to blame?

88_pacifica
11-13-2008, 12:39 PM
Are the headers quite a bit bigger and the thermostat significantly cooler? That could add to a higher percentage of unburnt fuel into the exhaust....

karlak
11-13-2008, 12:47 PM
thermostat

JamesL
11-13-2008, 12:52 PM
Make sure the the car is hot when you bring it in. I'd go up on the thermostat especially for winter in MD.

ScottD
11-13-2008, 12:59 PM
Stock thermostat is 195. I put the 180 in.

The headers are not huge by any means.

http://i357.photobucket.com/albums/oo19/scottdrega/headers5.jpg

http://i357.photobucket.com/albums/oo19/scottdrega/headers2.jpg

88_pacifica
11-13-2008, 01:05 PM
Stock thermostat is 195. I put the 180 in.

The headers are not huge by any means.

Yep, sounds like the thermostat. I would also run the highest octane you can(even a little additive for emmissions)and be sure the IAC is good and clean. Also, be sure to make sure that the idle isn't too low as that can hurt emissions as well...

ScottD
11-13-2008, 01:15 PM
It seems to idle fine, if the IAC is held in with loctite'd screws like on the TM's I'm not touching it! :-)

I did run 93 octane on this last test.

Thanks for all the feedback so far!

contraption22
11-13-2008, 01:37 PM
Defintitely put in the hotter thermostat. If the puter reads anything like my '93 TBI, coolant temp has a significant effect on idle speed, fuel mixture, etc.

If you have the option, get a Stant SUPERstat or quivalent. Its a couple bucks more, but it maintains coolant temperature better than a standard stat. You'd think that they would just make all their stats as good as the Superstats, but no.

Also, did you get a printout that tells you why it failed? Often you can tell by the readout of the emissions machine what the problem may be.

shelbydave
11-13-2008, 01:52 PM
Did you move the cat from the original position? If you moved it farther back on the exhaust, it may not be getting up to temp.

turbovanmanČ
11-13-2008, 01:54 PM
Readings? You failed Nox, right? My guess, :eyebrows:

I bet 100% the cat, Catco's are garbage, they are on the lower scale of crap, I bet they use the thinnest layer of coatings possible. 90's Dodges need a Walker Super cat, I have a number to use or OEM.

Juggy
11-13-2008, 02:09 PM
is that a TBI dakota??

if so whered you get those headers??? i can only find 92+ magnum stuff!!!
any gains?? what else have you done to it? dont mean to hijack!!

but yeah I had a catco 2.5" cat on the 3.0 back in the day and it wouldnt pass E test...kept failing the last one, it was blowing the reading away like 2400-2500ppm

ScottD
11-13-2008, 02:48 PM
First time just failed Nox. That was an 80 degree day.

Today failed Hydrocarbon and Nox. It was raining today though and Nox was down significantly though not enough to pass. Today's temp 43 degrees at time of test.

Cat is in the stock location. All EGR stuff is hooked up. I've heard of Catcos failing on other turbo Dodges.

Thanks Mike for the thermostat tip. They charge more because people are paying it. Stant must be a capitalist corporation and not non-profit, damn them :-)

Headers came from Summit. A little pricey but well worth. Mods are pretty basic, 180 t-stat, 2.5 cat going into 3 inch cat back, cold air induction, K&N drop, and the headers. Mods made a nice difference.

89ShelbyGuy
11-13-2008, 02:57 PM
i know when my pops has an old carbed omni, it would'nt pass, so we took it to my cousin, he adjusted something on the carb,,the car ran like crap...took it there and passed with flying colors...then after it was done, he readjusted the carb in the parking lot and we drove off...

contraption22
11-13-2008, 03:33 PM
Thanks Mike for the thermostat tip. They charge more because people are paying it. Stant must be a capitalist corporation and not non-profit, damn them :-)

Haha... what I meant was, when you have the capability of building a better product for a fair price, why would they want to put their good name on a lesser product?

Obviously it must be profitable for them or they wouldn't do it I guess....

but anyway... thats off topic. ;)

turbovanmanČ
11-13-2008, 03:33 PM
180 stat won't cause NOx, it will help so leave that alone. Put this cat in and it will fly thru-

You have a choice of good Walker Supercats, 2.5 inch #15146 or 3 inch #15147 and if you want to spend a little extra, this cat will pass anything, even Rotaries, 2.5 inch #15067 and 3 inch #15068.

JDAWG
11-13-2008, 03:48 PM
Take tags off till 2010, its only a year away.

Scott I have take out AIS motors plenty of time with no problems

ekimdam
11-13-2008, 04:06 PM
Thermostat then cat is the order I'd try.

As far as using the highest octane possible, I'd have to disagree. Use the lowest octane you can get (prolly 87) and get the thing as hot as you can without killing it.

Higher octane fuel, while good for anti-knock and making more power, doesn't do a good job of getting completely burned up in lower compression engines and has a greater probability of leaving the cylinder as unburned/partially burnt fuel. Also, you need a lot more heat/compression (energy) to burn higher octane fuel more completely or more time for it burn.


High octane = slow burning
Low octane = faster burning

ScottD
11-13-2008, 04:09 PM
I can get historic tags for it this January. MD law says 20 "model" years. I just renewed the tags though, which is why I want to get it through.

The cat is welded in. I really don't want to go through taking that out.

Putting a stock 195 t-stat in isn't a big deal.

I'd read some articles on line suggesting using 93, which I did. Most of the time I run it on 87.

black86glhs
11-13-2008, 04:27 PM
Have you checked the timing? To run 93 octane, you would need to bump the timing up slightly to take advantage of the octane. The other thing is the EGR system. It may be hooked up, but does it flow enough to actually work. Apply vacuum to the valve at idle and see if you can get the engine to stall. If it doesn't, you have a blockage of some sort somewhere in the EGR system.

shadow88
11-13-2008, 08:23 PM
My vote will always go with the cheap aftermarket cat.:nod:

contraption22
11-13-2008, 08:33 PM
Might also want to try over-inflating the rear tires. It should reduce drag on the rollers.

shelbydave
11-13-2008, 09:59 PM
Might also want to try over-inflating the rear tires. It should reduce drag on the rollers.

Do they actually put the car on a machine like a dyno? Holy Crap! In NC they just stuffed a sniffer up the tailpipe, and checked at different rpm's

The equipment got too expensive, so now it's just OBDII :banana-mario:

Pat
11-13-2008, 11:08 PM
My vote will always go with the cheap aftermarket cat.:nod:

+1 :thumb:

rosie
11-13-2008, 11:16 PM
My 90 Dakota Sport passed emissions 2 years ago with 193k on it and the ORIGINAL cat.

Now, after putting on Edelbrock headers, a new EGR valve, new 02 sensor, a 180 degree t-stat, and a Catco cat, it has failed twice. The plugs, wires, cap and rotor all have under 10k on them.

Thoughts? Is the Catco cat to blame?

I didn't read through everything (sorry) but I don't use anything but a Magnaflow OBD2 cat. Cleans up everything! Dropped my nox over 1000, and passed clean with the 3" from the collector back. Summit sells them and you can catch them on EBAY too but about the same price as summit and you'll have confidence in who you're buying it from.

black86glhs
11-13-2008, 11:28 PM
+1000 on the Magnaflow. The last Catco's I put on my Caprice only lasted 6 months before they were rattling.:mad::mad:

rosie
11-13-2008, 11:32 PM
Catco used to be the poop till Highflow Magnaflow's became the affordable. Ahhhh those were the days....

ScottD
11-14-2008, 12:06 AM
I've never had a problem with a Catco on a TD.

Bite me Pat, no more tow dolly for you!!!

contraption22
11-14-2008, 12:12 AM
Do they actually put the car on a machine like a dyno? Holy Crap! In NC they just stuffed a sniffer up the tailpipe, and checked at different rpm's

The equipment got too expensive, so now it's just OBDII :banana-mario:

Well in PA they put the OBDI cars on a dyno to test em. I dunno about MD.

88C/S
11-14-2008, 12:59 AM
ditto for CA.

zin
11-14-2008, 06:47 AM
Have you checked the timing? To run 93 octane, you would need to bump the timing up slightly to take advantage of the octane. The other thing is the EGR system. It may be hooked up, but does it flow enough to actually work. Apply vacuum to the valve at idle and see if you can get the engine to stall. If it doesn't, you have a blockage of some sort somewhere in the EGR system.

You may be onto something here, the EGR has everything to do with NOX and the addition of the header/cat back will lower the back pressure and I think you have a back pressure type EGR so it could be screwing with things, if it's computer controlled, probably not so much.

The stat will effect hydrocarbons and/or CO, CO usually means too little O2 (rich mix), Hydrocarbons are normally the result of a misfire (ignition/vacuum leak, etc), dumping raw, unburnt fuel into the exhaust. Lastly, a good cat will cover for alot of these conditions, so that may be where you have to go...

If you have the option, retard the timing as much as they will allow (within reason of course!), it'll run like crap and put heat in the exhaust, but it'll lower emissions across the board and might help light off the cat due to the extra heat retarded timing will put in the exhaust. If you can do it, don't leave it like that too long. BTW, this is the same basic trick we here in CA used to do when this kind of thing happened, at least until coil packs and limits on how retarded timing was allowed to be (2* now IIRC).

Best of Luck!

Mike

rosie
11-14-2008, 08:46 AM
You may be onto something here, the EGR has everything to do with NOX and the addition of the header/cat back will lower the back pressure and I think you have a back pressure type EGR so it could be screwing with things, if it's computer controlled, probably not so much.

The stat will effect hydrocarbons and/or CO, CO usually means too little O2 (rich mix), Hydrocarbons are normally the result of a misfire (ignition/vacuum leak, etc), dumping raw, unburnt fuel into the exhaust. Lastly, a good cat will cover for alot of these conditions, so that may be where you have to go...

If you have the option, retard the timing as much as they will allow (within reason of course!), it'll run like crap and put heat in the exhaust, but it'll lower emissions across the board and might help light off the cat due to the extra heat retarded timing will put in the exhaust. If you can do it, don't leave it like that too long. BTW, this is the same basic trick we here in CA used to do when this kind of thing happened, at least until coil packs and limits on how retarded timing was allowed to be (2* now IIRC).

Best of Luck!

Mike

They check the timing to make sure you don't do that.

JDAWG
11-14-2008, 01:12 PM
They check the timing to make sure you don't do that.

not in md, they do a visual check and cant have the check engine light on. Depends on the year if they put it on the rollers. My 95 S15 I had dropped severely (before adjustable suspension), like you couldnt slide a pack of cigs under the frame. So I rolled up and they said it wont go on the dyno, I said I dont care, Ill drag my bumper up on it. They said no, if you damage it its our fault. So he made sure I had exhaust, popped the hood and made sure (his words) "I had all my emissions stuff" (he had no clue what he was looking at). Closed the hood and handed me a waiver.

bris09
11-14-2008, 05:59 PM
NOx are generally a byproduct of high combustion temps. The hotter the flame the higher the NOx. Adding fuel will cool the flame temperature thus reducing the NOx. High octane fuel burns slower than lower octane which means a cooler flame, that's why it is recommended to use higher octane fuel for the emissions test.

With the exhaust you have my guess would be that it is running lean, thus the cylinder temps are higher. Any chance you can give it a little more fuel? This will lower the cylinder temps and the NOx. If that is the problem.

Another possiblity is with the headers, high flow cat, and bigger exhaust that the cat is not getter hot enough to work properly. Don't have much advise to give if that is the case.

I don't know enough about the Catco cats to comments on them, I've only used the Magnaflow cats.

Another option would be to add some alcohol to the gas. Alcohol does not burn as hot as gas and burns cleaner so it will lower the the emissions. I can't tell you how much to use though, depends on how far out you are. If you are way out this is not even an option as you can only get away with adding so much without doing harm to other components.

Sure glad we only have the visual, gas cap, and OBDII test.

black86glhs
11-14-2008, 06:13 PM
It isn't really a case of burning slower, it is that it doesn't ignite at as low of a temp as regular. That way any hot spots(glowing pieces of carbon) don't create another ignition sources. But you got the idea.

zin
11-14-2008, 06:40 PM
They check the timing to make sure you don't do that.

Yeah, but you can have a variance of up to 2*, so you can be two up or down from what's listed, so if you are on the edge, retard it 2 from "stock" and it might get you to pass.

Mike

zin
11-14-2008, 07:00 PM
Another option would be to add some alcohol to the gas. Alcohol does not burn as hot as gas and burns cleaner so it will lower the the emissions. I can't tell you how much to use though, depends on how far out you are. If you are way out this is not even an option as you can only get away with adding so much without doing harm to other components.

The alky will lean out the mix, which might help if it's running rich. This is because the A/F for alky is about 7:1 vs 14.7:1 for gas. So long as you are using de-nautured alky, (ethanol w/ a small amount of Methanol added so you don't drink it), it shouldn't be too harmful to other pieces (rubber etc). The possible catch is that most gas already has about 15% added to it, so adding more might not do too much...

Mike

ScottD
11-15-2008, 09:43 AM
Thanks for all the feedback.

In MD they don't check the timing. So I could retard the timing some. I seem to remember checking the timing before and it was fine. If the timing was off it wouldn't run as well as it does.

After reading some of the posts on here I'm inclined to think that it is running rich because of the t-stat. I was hoping that after adding the headers and exhaust that my gas mileage would go up a little bit. It really hasn't changed much at all. Secondly, the fact that I passed hydrocarbons on an 80 degree day but failed them on the 43 degree day is interesting. I would think that's an indication of it running too rich.

turbovanmanČ
11-15-2008, 02:44 PM
Hyrdrocarbon's aren't an indicator of running rich unless the CO is high, HC's are from a colder engine, misfire or bad cylinder design.

Usually a 180 stat will worsen your MPG unless you have a matching computer chip.

NOx is formed when lean, so your not rich. Rich will show little or no NOx.


Check your egr, get a vacuum gauge and hook up to the egr hose, route it so you can see it and go for a drive, under light cruise you should see 5-10" of vacuum, if not, you have a defective solenoid, transducer or not enough backpressure. If you have vacuum, then apply vaccum to the egr at idle, the engine should start to run rough, if not, the passage is plugged up.

black86glhs
11-15-2008, 02:45 PM
Hyrdrocarbon's aren't an indicator of running rich unless the CO is high, HC's are from a colder engine, misfire or bad cylinder design.

Usually a 180 stat will worsen your MPG unless you have a matching computer chip.

NOx is formed when lean, so your not rich. Rich will show little or no NOx.


Check your egr, get a vacuum gauge and hook up to the egr hose, route it so you can see it and go for a drive, under light cruise you should see 5-10" of vacuum, if not, you have a defective solenoid, transducer or not enough backpressure. If you have vacuum, then apply vaccum to the egr at idle, the engine should start to run rough, if not, the passage is plugged up.
I said that earlier......hmmmm.

turbovanmanČ
11-15-2008, 02:47 PM
I said that earlier......hmmmm.

Sooooooo, ;)


Just reiterating as he seems to have his mind set on running rich. :D

black86glhs
11-15-2008, 02:59 PM
Sooooooo, ;)


Just reiterating as he seems to have his mind set on running rich. :D
Well......I didn't state it as well as you and missed the transducer/solenoid part.:hail: I was thinking the same about the mixture. Rich would cool it off.
In theory it could be an injector that doesn't spray correctly(A little lean). The EGR. Engine temp(T-stat temp). Fuel supply(not pressure, volume). Weak ignition or worn plugs.

Pat
11-15-2008, 04:11 PM
Thanks for all the feedback.

In MD they don't check the timing. So I could retard the timing some. I seem to remember checking the timing before and it was fine. If the timing was off it wouldn't run as well as it does.

After reading some of the posts on here I'm inclined to think that it is running rich because of the t-stat. I was hoping that after adding the headers and exhaust that my gas mileage would go up a little bit. It really hasn't changed much at all. Secondly, the fact that I passed hydrocarbons on an 80 degree day but failed them on the 43 degree day is interesting. I would think that's an indication of it running too rich.


Double or nothing?

rosie
11-17-2008, 12:08 AM
Double or nothing?

Sooooooo he failed on HC on a cold day. Failed on Nox on a warm day. What say you smog techs?

Anywho, retard your timing and make sure the car is running the whole time before you get there so your catco (that I disammend) is nice and hot. I also recommend 25% alcohol (straight from CVS) in your tank. It doesn't lean out your fuel possibly causing nox. If that was what it did I don't think "we" would be running it as "alky injection". Good luck.

Pat
11-17-2008, 07:05 AM
Sooooooo he failed on HC on a cold day. Failed on Nox on a warm day. What say you smog techs?

Anywho, retard your timing and make sure the car is running the whole time before you get there so your catco (that I disammend) is nice and hot. I also recommend 25% alcohol (straight from CVS) in your tank. It doesn't lean out your fuel possibly causing nox. If that was what it did I don't think "we" would be running it as "alky injection". Good luck.

Smog tech I am not, but Scott and I have a friendly wager on his trucks emmissions test. If I remember correctly, it failed Nox both times he ran it.

rosie
11-18-2008, 09:55 PM
Just re read some posts and zin was the one talking about hydrocarbons and then my brain mixed it with failing with it cold out. I was making and --- u me tion. Sorry. Won't apoligize for being a smart arse though because it might make me gun shy....

But for realy, though, with the backpressure actuated EGR valves alot of cars have and all aftermarket EGR's (that I have seen in my shops) and now a free'r flowing exhaust you are going to have problems with Nox because the backpressure isn't lifting the valve... Unless you put in that Magnaflow all those cool guys are talking about or run a vacuum actuated EGR which I haven't been able to find. Maybe a JY one that is cleanish?

I don't know when they quit making them but it became a PITA to figure out if they were bad because you couldn't use a vacuum pump on them to see if they were leaking or wouldn't lift or would change the idle when it did lift!

Badger
11-19-2008, 03:14 AM
I know on the "dodge garage" site by Donovan it specifically says that catco cats are garbage like many on here have said.

just throwing that out there.

ScottD
01-05-2009, 10:51 PM
I have an update on this.

I changed the t-stat to a 195 but it still seemed to be running at the same temperature. I thought maybe the CTS had failed so I put the scanner on it tonight.

It was reading a consistent 170-172 degrees at idle. The fan seemed to be going full bore. Could the thermostatic switch on the fan clutch have failed?

I found out I can't get historic plates til next year so I have to get this resolved.

rosie
01-06-2009, 12:40 AM
Does the fan spin freely of the clutch at idle or is it locked?

JDAWG
01-06-2009, 12:50 AM
Does the fan spin freely of the clutch at idle or is it locked?

you mean with the engine off right?

Scott I dicked them around for a year with my car. I didnt fix anythin on it for close to a year. Just kept taking it in, pay my money, and get another date in the mail. Was kinda puttin it off till I got another car so I could tear it apart. But I know what you mean, you want it to run right. Just a fyi.

ScottD
01-06-2009, 01:29 AM
Does the fan spin freely of the clutch at idle or is it locked?

Not sure what you mean. At idle I can see the clutch spinning with the fan. Should the clutch not be spinning at idle? Basically what I read in the FSM was the fan should always spin, but at idle it should spin at a lower speed.

JDAWG
01-06-2009, 01:41 AM
http://en.wikipedia.org/wiki/Fan_clutch

can you spin it with the truck off? Most of the time when they ares just locked to the crank you get alot of vibration, like sitting in the cab it vibrates alot

ScottD
01-06-2009, 08:43 AM
The truck has 201k on it, it vibrates just from that LOL

I'll take a look at it tonight and see if it spins.

turbovanmanČ
01-06-2009, 01:55 PM
When the truck is cold, it should be stiff to turn-engine OFF. After it gets to operating temp, it should freewheel, engine OFF. If its almost impossible to turn or locked, and your truck sounds like an airplane reading to take off all the time, its junk. Buy OEM, the aftermarket ones are junk.

ScottD
01-06-2009, 02:13 PM
I went home and turned the fan while cold, seems ok. Will have to see how it spins after it is warmed up.

Could the thermostatic switch just have failed and the fan is running on high speed all the time?

turbovanmanČ
01-06-2009, 02:20 PM
I went home and turned the fan while cold, seems ok. Will have to see how it spins after it is warmed up.

Could the thermostatic switch just have failed and the fan is running on high speed all the time?

Its possible but you'll now after its warmed up.

ScottD
01-06-2009, 09:04 PM
Been doing some more reading of the FSM. I wonder if another problem is the EGR valve isn't opening because after installing the headers, high flow cat and 3 inch cat back I reduced backpressure too much.

From the FSM: "When the EGR solenoid is not energized and exhaust gas back pressure entering EGR valve inlet is high enough, back pressure holds vacuum transducer bleed valve closed. This allows vacuum to activate and operate the EGR valve."

I might have two separate issues here.

turbovanmanČ
01-06-2009, 09:19 PM
Been doing some more reading of the FSM. I wonder if another problem is the EGR valve isn't opening because after installing the headers, high flow cat and 3 inch cat back I reduced backpressure too much.

From the FSM: "When the EGR solenoid is not energized and exhaust gas back pressure entering EGR valve inlet is high enough, back pressure holds vacuum transducer bleed valve closed. This allows vacuum to activate and operate the EGR valve."

I might have two separate issues here.

Easy too test, hook up a vac/pressure guage to the transducer and go for a drive, you should see 1-5 psi. Also hook up to the egr line and go for a drive, see what kind of vacuum you see reaching the valve.

A good cat will clean up Nox, even if your egr isn't working.

shelbydave
01-06-2009, 10:29 PM
Do they test at different RPMs? I don't think the EGR operates at idle...

turbovanmanČ
01-06-2009, 11:04 PM
Do they test at different RPMs? I don't think the EGR operates at idle...

Nox isn't produced at idle unless you have a lean misfire or very lean mixture, and if it is in a normal running engine, its barely readable and yes, EGR's don't work at idle, if they did, you'd have a vacuum leak.

shelbydave
01-07-2009, 08:28 AM
Nox isn't produced at idle unless you have a lean misfire or very lean mixture, and if it is in a normal running engine, its barely readable and yes, EGR's don't work at idle, if they did, you'd have a vacuum leak.

I did once!! On my carbed SC. I removed the EGR, and blocked the tube, replaced the EGR, and all was fine after that!!

Since they only tested at idle, the car passed the tampering (visual) inspection, AND the sniff test without an EGR.;)

mech1nxh
01-07-2009, 09:07 AM
Also, did you get a printout that tells you why it failed? Often you can tell by the readout of the emissions machine what the problem may be.

Readings please,
you posted a failure of NOX and HC on the second test?...
Co & O2 readings?
thx

ScottD
01-07-2009, 09:17 AM
I'll post the readings tonight.

We have treadmill tests here in MD where the RPM varies.

THANK YOU FOR ALL THE INPUT, I REALLY APPRECIATE IT!

turbovanmanČ
01-07-2009, 02:12 PM
I did once!! On my carbed SC. I removed the EGR, and blocked the tube, replaced the EGR, and all was fine after that!!

Since they only tested at idle, the car passed the tampering (visual) inspection, AND the sniff test without an EGR.;)

Yep, the good old block off plate, :nod: We used to have to do that here but they stopped looking under the hood so it didn't matter anymore, :clap:

ScottD
01-07-2009, 02:28 PM
Here are the emissions reports.

turbovanmanČ
01-07-2009, 03:55 PM
Your test is the same as ours, :thumb:

Based on it, it one or 2 things, the ox sensor or the cat, but if the ox is working, that cat isn't doing much, :(

ScottD
01-07-2009, 04:10 PM
The 02 sensor is a brand new Mopar unit that has maybe 3 or 4k on it.

The cat is a Catco .....

shelbydave
01-07-2009, 04:15 PM
I think it's already been said that Catco cats aren't really good...

turbovanmanČ
01-07-2009, 06:55 PM
The 02 sensor is a brand new Mopar unit that has maybe 3 or 4k on it.

The cat is a Catco .....

Even new, they can be bad, its rare but does happen. Get it checked, if its ok, then you know the answer.

ScottD
01-12-2009, 02:12 PM
Failed again. HC limit is 2.40, this test recorded 2.49. NOX limit is 3.0, this test recorded 3.48.

I did put in a new t-stat. The truck was running at 170degrees, now it is running at 188.

According to my scanner, the 02 sensor is working. It reads 1.0V at WOT and jumps around at part throttle. It reads minimal voltage at idle.

turbovanmanČ
01-12-2009, 02:19 PM
Quit messing around and put a real cat in, :D

Use the numbers below or OEM. If you use anything else, you'll be posting up again that it failed.


You have a choice of good Walker Supercats, 2.5 inch #15146 or 3 inch #15147 and if you want to spend a little extra, this cat will pass anything, even Rotaries, 2.5 inch #15067 and 3 inch #15068.

shelbydave
01-12-2009, 03:14 PM
I really think it's the CAT also. If you want to run the Catco, and it's not welded in, just go to Advance, and pick up a replacement. Get it tested, and if it passes, take it back out, put the Catco back in, and use the new one once a year for emissions testing.

ScottD
01-12-2009, 04:01 PM
The PITA part of all this is I had a buddy weld the catco cat in when I installed it, so changing it will be a pain.

I agree though that seems to be the problem. If I put another cat on and it passes I will want to sue Catco!!!!

turbovanmanČ
01-12-2009, 04:12 PM
The PITA part of all this is I had a buddy weld the catco cat in when I installed it, so changing it will be a pain.

I agree though that seems to be the problem. If I put another cat on and it passes I will want to sue Catco!!!!

Trouble is, Catco is low end of the scale, for alot of cars/trucks they work but yours needs a good cat, its not really Catco's fault.

mopar-tech
01-19-2009, 11:40 AM
The CAT is the problem, epic fail on those.

We went through this with Genesky's Spirit R/T, EPIC FAIL with aftermarket Autozone cat, flew right through with 10+ year old Mopar unit.

The aftermarket cats have very small amounts of platinum and plaidium compared to ma mopars OEM units to keep costs down.

Do the cheap aftermarket ones work? Yes but not very well and not very long.

RoadWarrior222
01-19-2009, 12:05 PM
Couple of thoughts

Does this truck get run much? Does it run for more than half hour at a time?

When you changed the EGR valve did you check/replace the tubing or anything? ... some vehicles like to clog it up.

What I would do to the thing, would be to put a bottle of 99% Isopropyl alcohol in the tank, take it for an hour drive, finishing that off with several 2nd gear WOT uphill pulls, then take it in that day or the day after before you clog everything up again by doing short trips to the store. If that don't fix it, with high NOx and HC the cat is shot.

If it's been burning oil, or using it mysteriously, the cat is clagged up from that, to attempt to clean it out enough to work again, drive it around for an hour, then engine brake down some long grades, fuel should be cut right back and you should be forcing fresh air through a hot cat which should be getting some of the coking off it.

turbovanmanČ
01-19-2009, 02:17 PM
Couple of thoughts

Does this truck get run much? Does it run for more than half hour at a time?

When you changed the EGR valve did you check/replace the tubing or anything? ... some vehicles like to clog it up.

What I would do to the thing, would be to put a bottle of 99% Isopropyl alcohol in the tank, take it for an hour drive, finishing that off with several 2nd gear WOT uphill pulls, then take it in that day or the day after before you clog everything up again by doing short trips to the store. If that don't fix it, with high NOx and HC the cat is shot.

If it's been burning oil, or using it mysteriously, the cat is clagged up from that, to attempt to clean it out enough to work again, drive it around for an hour, then engine brake down some long grades, fuel should be cut right back and you should be forcing fresh air through a hot cat which should be getting some of the coking off it.

Alcohol in the tank makes it run hotter, which will increase NOx. If you look at his trace, its awful, all over the map, proving a fuel control issue or bad cat, and we've crudely narrowed down his ox is ok.

RoadWarrior222
01-19-2009, 02:48 PM
IPA is really good at cleaning up injectors and emissions components though, (And is the major constituent of many off the shelf cleaners) and seems to boost octane quite a bit more than other alcohols. Also seems to decarb an engine somewhat, maybe not totally, but I think it helps take off all the flaky glowing edges.

ScottD
01-19-2009, 03:19 PM
I drive the truck at 4 days a week, it gets driven all the time. I'm about to hop into it to go grab lunch.

I had all the EGR tubing off when I put the headers on and they were fine. Also cleaned out the passage in the manifold.

Bought a Magnaflow cat which I read good things about and am going to install it this week, hopefully that will get it through. Just kinda frustrating that the reason I put the Catco on there in the first place was because I thought the original cat might be getting iffy with almost 200k on it!


Couple of thoughts

Does this truck get run much? Does it run for more than half hour at a time?

When you changed the EGR valve did you check/replace the tubing or anything? ... some vehicles like to clog it up.

What I would do to the thing, would be to put a bottle of 99% Isopropyl alcohol in the tank, take it for an hour drive, finishing that off with several 2nd gear WOT uphill pulls, then take it in that day or the day after before you clog everything up again by doing short trips to the store. If that don't fix it, with high NOx and HC the cat is shot.

If it's been burning oil, or using it mysteriously, the cat is clagged up from that, to attempt to clean it out enough to work again, drive it around for an hour, then engine brake down some long grades, fuel should be cut right back and you should be forcing fresh air through a hot cat which should be getting some of the coking off it.

turbovanmanČ
01-19-2009, 03:22 PM
Bought a Magnaflow cat which I read good things about and am going to install it this week, hopefully that will get it through. !

I am sorry you don't read very well, those cats are NOT much better, I've told you this numerous times. I DO THIS for a living, I know what cats work. Good luck, :thumb:

ScottD
01-19-2009, 08:12 PM
Simon - I read what you suggested and appreciate the help. The one Walker cat I was interested in that you suggested doesn't have an air tube and it was too long to fit where it needs to go, the Magnaflow is a compromise.

turbovanmanČ
01-19-2009, 09:09 PM
why do you need an air tube? You shouldn't have an air pump? if you do, there are other numbers that work.

Magnaflow's are also bottom of the cat chain, :(

ScottD
01-20-2009, 10:28 AM
Yep, I have an air pump.

I did a google search and found LOTS of people had problems with catco on various makes. I did the same search for Magnaflow and didn't see nearly as many problems and a friend's brother worked at an exhaust shop in NY and that was all they installed was Magnaflows, so I'm hoping it does the trick. I'll find out soon enough ...

ScottD
01-23-2009, 03:24 PM
IT PASSED!

I also just want to say THANK YOU to everyone who gave some advice.

Ultimately it was the Catco cat that was the primary culprit.

turbovanmanČ
01-23-2009, 05:17 PM
Good to hear. :clap:

Do you do this every year? you might be going thru this again, I hope not, :(

shelbydave
01-23-2009, 10:24 PM
Good to hear. :clap:

Do you do this every year? you might be going thru this again, I hope not, :(

I've been in the same boat with cheap cats. They'll get you 2 inspections at best, if the inspections are annual. :nod:

ScottD
01-24-2009, 10:37 AM
It is every two years BUT next year I can get historic plates and avoid the emissions test altogether.

The HC dropped to 1.94 (the limit is 2.4) and the NOX dropped to 2.83 (the limit is 3.0) so it might be close the next time. I'll probably just put historic plates on it by then, regular tags cost me $180 every two years and I still have to do emissions and historics cost $51 w/ no emissions test.