Please help answer this Catalytic converter question? Thank You

jmonica

Original poster
Member
Apr 2, 2013
384
Hamburg, NJ
So I have one day to fix about 437 problems with my Envoy. Ok maybe about 11 things from wheel hubs, rebuilding calipers, thermostat, catalytic converter and downstream 02 Sensor. front ball joints. Anti Sway Bar end links, and a time consuming install on a new gas cap. It's my one and only day to it, tomorrow is it and I wont have another chance for quite a while.

So I've been stock piling the parts I will need and have everything ready to go. I am going to begin a 24 hour thrash on it and try to fix every system and problem it has in one 24 hour period. Case of redbull, three packs of smokes and a my Chilton manual are all that I'm taking into this battle. One of the parts that I bought is a catalytic converter. When I just checked my order, it says that it fits a 2005 Envoy with a 113" wheelbase. But mine is a 2006 Envoy which it indicates it will not fit.

Does anyone have any idea if it's true and I really wont be able to make it work? Or if I am actually, really totally hosed? Will it really not fit? I"m so bummed if it won't work / fit. Thanks!
 

aaserv

Member
Dec 1, 2019
408
N of Baton Rouge, La.
Did you get just the converter or connecting pipes also? If you got just the converter your probably ok . If you got the 1 that comes with the connecting pipes...I dunno.
Would be interested to know how you know you need BOTH a CC and the #2 sensor. How do condemn a CC with a bad sensor and vice versa?
 

jmonica

Original poster
Member
Apr 2, 2013
384
Hamburg, NJ
Hi, Thanks for your reply. I'm getting a high voltage code on the downstream sensor. I had problems installing it like 6 years ago and had to basically make my own connectors for it etc. I am desperate to get this car inspected like tomorrow.

So I got the whole pipe. My existing one is not pretty and given the limited amount of time I have to do a lot of work on the car, the extra cost was worth the time savings of not having to weld on a generic one. I can move on to bigger and better things, like the wheel hubs, rear wheel bearings. Rebuilding the front calipers, a new thermostat, the ball joints, new pads and rotors all around and I noticed today my brake pedal goes almost to the floor if I hold pressure on it during a stop so now I've added a master cylinder to the list as well. Sway bar links and bushings. New power steering lines, rear shock bushings. I have lot to do. It's going to be a redbull fueled 24 hour thrash!

I know that I need a catalytic converter because when I had removed it to swap the transmission, I could see that the honeycomb material inside of it was all broken to little pieces.
So for the minimal cost of the O2 sensor, I have a chance to put the wiring back the way it goes at the same time I install the new cat, hopefully pass emissions and be done with it. I can't delay the inspection even one more day so it's worth it to me to eliminate any unknowns if the cost is minimal. I've already tested the wiring to the O2 sensor and the wire test checked out. I had .3 volts, ground and battery voltage to the sensor, but bank 1 sensor 2 still showing a fault. 9/10 times a P0138 is a failed sensor so for $20, and having tested the wiring harness to the sensor, I didn't even blink an eye when I weighed the cost of it against failing the inspection. I don't generally throw parts at a problem but the evidence was leaning towards a sensor failure which was btw a cheap Chinese one I had installed about 6 years ago. I feel like I got my moneys worth out of it. I knew what i was buying when I purchased it.

Was there something else that I should have tested before blowing the $20 on the sensor?

So do you think I've chosen the right path towards success? :undecided:
 
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Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
As @aaserv asked, is the cat you bought a universal splice-in type or is it the complete one with pipes from manifold to rear exit?

I have a feeling you bought the complete cat with pipes. Looking at the images on RA, the outlet pipe connections are different. The 02-05 have a flat gasket while the 06-07 have a ball and socket type connection with a gasket.

This is the 02-05:

And the 06-07:
 
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aaserv

Member
Dec 1, 2019
408
N of Baton Rouge, La.
Eyeballing the CC certainly explains how you know its bad...lol Hoping you find away to get it mounted but it doesnt sound good if you have the pipes also.
I know you said tomorrow is your dead last day to get it done so this may be all for nothing but where Im from we have the strictest emissions testing outside of Calif. that im aware of. However there is , i think federal law but maybe my state....that if you fail only the emissions test you can apply for a hardship extension which will give you like 90-120 more to get the emissions problems done. This is due to how much these repairs can cost and the hardship it can put on poor people....like me!! The way you do it here is to bring the car to the actual place where they do the training/testing for all the inspection stations and they look it over and grant you the extension.. I know some shops around here are not even aware of this provision so hopefully its worth looking into in your case...
 
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jmonica

Original poster
Member
Apr 2, 2013
384
Hamburg, NJ
As @aaserv asked, is the cat you bought a universal splice-in type or is it the complete one with pipes from manifold to rear exit?

I have a feeling you bought the complete cat with pipes. Looking at the images on RA, the outlet pipe connections are different. The 02-05 have a flat gasket while the 06-07 have a ball and socket type connection with a gasket.

This is the 02-05:

And the 06-07:
As @aaserv asked, is the cat you bought a universal splice-in type or is it the complete one with pipes from manifold to rear exit?

I have a feeling you bought the complete cat with pipes. Looking at the images on RA, the outlet pipe connections are different. The 02-05 have a flat gasket while the 06-07 have a ball and socket type connection with a gasket.

This is the 02-05:

And the 06-07:
Thank You Mooseman. As always, you are correct. I didn't have a chance at work to dig in and figure out if I had made a mistake or not and needed to know before I left work if it was going to be the wrong part as it would determine whether or not I still needed to take the day off tomorrow. The cat was one of the more important things so no use burning the vacation day if I have to take another one once I get the new cat. Obviously I don't need to take a day off to install just the cat. You'd have to be a slow moving mofo if it took that long. It's the Alignment, then the DMV, then the line at the inspection station that requires all of the time.
So i took a snap of the flange so someone else might be able to see why the '05 cat wont work on the "06 and vice versa. Mine (the '06 SLT) actually has the flat flange and the one I got has the rounded end as shown in the photo. Now trying to think of away to improvise and get away with finishing it tomorrow, my best solution would be to cut and weld the proper flange on the new pipe. There is that 1 foot section of flex pipe down there which might give me a little but if wiggle room if the cut and weld doesn't produce the exact same dimensions I would hope. Worst case, I waste the new one and just have to buy another. Best case, it actually works so I think I'll take a swing at it. As always I will report back. Just please don't laugh at my welds. I only really seem to struggle with round pipes. Not sure if its inherently just more difficult or if my lack of coordination just shines brighter on a curved surface. In any case, I'm self taught on the welder so nobody to bounce ideas off and so I usually just do the best I can and hope it works out. Thank You again as always man! I appreciate your help very much. Man I just noticed the factory welds.
Not very pretty but i guess who cares what they look like if they hold and do their job.

Thats 20200225_191341[5801].jpg
 
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jmonica

Original poster
Member
Apr 2, 2013
384
Hamburg, NJ
Eyeballing the CC certainly explains how you know its bad...lol Hoping you find away to get it mounted but it doesnt sound good if you have the pipes also.
I know you said tomorrow is your dead last day to get it done so this may be all for nothing but where Im from we have the strictest emissions testing outside of Calif. that im aware of. However there is , i think federal law but maybe my state....that if you fail only the emissions test you can apply for a hardship extension which will give you like 90-120 more to get the emissions problems done. This is due to how much these repairs can cost and the hardship it can put on poor people....like me!! The way you do it here is to bring the car to the actual place where they do the training/testing for all the inspection stations and they look it over and grant you the extension.. I know some shops around here are not even aware of this provision so hopefully its worth looking into in your case...
Thanks AAServ. Yep I screwed up and bought the wrong pipe. Hate when that happens! :smile: The reason tomorrow is my drop dead date isn't really because my tags expire or anything. Its because work is going to get super busy for the next 3 or 4 weeks and won't have a single day off for that long. I crashed my DD a few weeks ago. Before that I have been getting the Envoy back in action after the trans went and it had been sitting for 18 months rotting away. My new car is so bad in the snow I had to sleep on the side of the highway during the first snow storm and was stranded for almost 11 hours. OK got to get the envoy going again, now~! I was taking my sweet arse time with it because I didn't need it but that got accelerated when I had the accident, realized I had no rental car provision on my insurance policy and so its been full on ever since. The registration is actually almost two years out of date and the inspection sticker shines brightly in green on the front window whereas the 2020 stickers are white. I'm basically a rolling bullseye. Every few nonths on my way to work, there's a stretch of road where a cop sits with his automatic plate reader and just waits for the computer to tell him who's driving on expired registration. I am on high alert since having to drive this thing unregistered man. That one section of road I call the gauntlet. If you are a month or so behind on the reg they wont impound your car. If you are two years behind, the car is going and I"m walking to work. Just this morning I pulled off the highway onto that same surface street. IN my rearview, a cop out of nowhere sitting dead stop behind me at what seemed like the longest GD red light in history. I just knew I was going down. I am almost home free too, damn. SO long story short, the dude never ran my tag I guess. It's a personalized one too, so if I were a cop and some dude like me had a personalized plate like that, I'd run his tag just out of spite I think.

SO my last ditch plan now is to cut the flange off the old pipe and put it on the new one, screw in the O2 sensor and just keep fingers crossed.

I'm in NJ and the inspection routine here is You go to a state run facility. BIG sign that reads, "CEL on, you Fail". But they do give you 30 days via a red temp sticker. At least it was red the last time I went through this for my uncle. The nice thing is, emissions is all that they check now. They used to do a full on "check everything" inspection but dropped that. You can roll in on 4 flat tires, one headlight, a shattered windscreen and making more noise than ten broken chainsaws, but as long as you pass the smog check, you pass. They do look under the car to make sure there's a cat which to me seems futile for obvious reasons, but maybe they have their reasons.
The other good thing is if you fail, you can fix the problem and get inspected as many times as you need to the same day. I failed once due to headlight mis-alignment on my plow lights before they stopped doing the full inspections. The guy said they were aimed too high. So i pulled out with my new ugly red sticker. Stopped at the exit, adjusted the lights down and went through again. That SOB failed me a second time too. Still too high. heheh Wow! Hey I can play this game all day buddy. The third time through was the charm. Now he has to scrap off that red sticker and put a real one on. Inspections are every two years here except for newer cars they give two and even four year extensions for those. Sorry for chewing your ear off.

Anyway, thanks for your help and guidance. Much appreciated!
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
Welding the old flange on the new pipe sounds like a good option unless your welding skills are such that it will leak. Or you take them to a shop and have them weld it on. Either way, just make sure the orientation is the same for the bolts to line up.

Keep at it. You'll get it done.
 
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jmonica

Original poster
Member
Apr 2, 2013
384
Hamburg, NJ
Welding the old flange on the new pipe sounds like a good option unless your welding skills are such that it will leak. Or you take them to a shop and have them weld it on. Either way, just make sure the orientation is the same for the bolts to line up.

Keep at it. You'll get it done.
Thanks Mooseman. I really don't know if I'd have the will to keep plugging along without yours and some other guys help like Maverick. He's been very cool to me too. It was supposed to be just a trans swap and ride off into the sunset. That was 4 months ago. hehe It's turned into so much more. There aren't very many parts left to replace though so I've got to be nearing the finish line soon!

I'm re-energized after a few days of having stepped away. Well, honestly I was on the internet all night researching it 10 minutes after I hit that wall and was ranting about giving up.

What's funny is the moment another problem pops up, I panic for a minute then immediately think, ok take it easy. Mooseman and/or Maverick, will know exactly what to do and will help me.
So with that in mind, for what it's worth, thank you for making me at least feel like I'm not stranded in some far off land all alone. My father was a mechanic his whole life. Anyway, now that I don't have him to ask questions to, or even a friend here in NJ to lend a hand, or bounce ideas off, You guys are my surrogate friends and my only human connection to talking about and messing with cars. So thanks for filling that void for me. Man I really am pathetic!!!

Your kindness and generosity with your time and knowledge really do make a difference to someone in my shoes.

OK enough of that sentimental crap! Now I'm off to pull an all-night thrash under the car! One ball joint to replace, 2 calipers to rebuild, thermostat to install, new Cat to weld, 2 speed sensors to replace, O2 sensor, drain and flush brake fluid for the first time in 300k miles. 4 new rotors, and something else on my list I forget. Oh I'm going to at least try to get the front end alignment a little closer. I'm waiting to have money for new tires before I have it aligned but its BAD now.

Obviously the bad BJ (no pun intended) prevents it from benefiting from a real alignment for now anyway. A long straight edge and a tape measure can get it close enough to not be dangerous to drive at least.

Oh of course a new problem cropped up today. It squeaks from the back of the vehicle while I am backing up. It feels like the parking brake is on or hung up but that's just the feeling I get. Who knows. It's on the list! Thanks
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
Hey, we've all been there. Heck, I remember when I got my first TB. It just needed an engine, ball joints and such. Let's just say that was a very long summer. In the end, I got lots of service out of that truck until the tranny died and it wasn't worth it anymore. Also learned a lot so now, it's as easy as pie to maintain and repair my current fleet. Also have a bunch of spare parts.
 
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jmonica

Original poster
Member
Apr 2, 2013
384
Hamburg, NJ
Hey, we've all been there. Heck, I remember when I got my first TB. It just needed an engine, ball joints and such. Let's just say that was a very long summer. In the end, I got lots of service out of that truck until the tranny died and it wasn't worth it anymore. Also learned a lot so now, it's as easy as pie to maintain and repair my current fleet. Also have a bunch of spare parts.
Yes! Thank god that you did too because you've shared your hard work with so many and for no reason other than to help others. I have hit or been hit by 5.5 deer in this envoy. $7-$8 in damage each time. I had an '04 before this one and one ran into me once. right at ,y door. The gouge in the side window from its antlers was so deep. I used to think my wife was a bad driver because she hit 2 in one year. By my third one i had to apologize to her. There's just nothing you can do. they just appear and then they get flung into the woods and its over in a blink. Ugg I can hear the sound of their hide sliding on the pavement. Anyway so I've been driving the same model Envoy for 15+ years everyday, I can tell the moment even the smallest little this is going wrong. Not because I am some great automotive detective but because I've been hearing the same hum everyday for a decade and a half. 90-120 minute commute to work and back every day. You just get used to hearing the same noises and when a different sound or the car does something just a little weird or different You know it.

Man I wish I had that black one back now. It looked nice when it was polished up with the polished rims etc,. I could probably buy one for $2500 bucks now. I remember doing that mutli-colored LED conversion for each of the climate controls, t looked good at night. Ahh those were the good old days. I did the leds in the steering wheel switches / buttons they are way too bright but they still all work after at least a decade. And now one will burn out tomorrow So sorry for blabbering on. I'm so bored. Gonna try to sleep for a few and get up at 5am to "Finish" fixing the envoy Ha! have a good night,. umm morning.
 
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Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
Ya, when you hit that wall, it's better to sleep than try to work through it because that's when accidents and mistakes happen.


:sleeping:
 
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