Free Auto advice from a certified mechanic !
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it's really that simple. you're lucky that you got an EX not an LX. on the LX the cat is part of the exhaust manifold and has to be replaced as a $800 unit. but ya, cuts yours off and weld on the new one.
Thanks, one question. I was looking at CATS on the autozone website & some of them were the CAT by itself, others had the front pipe which runs from the exhaust manifold to the CAT already attached? Any significance to this or just for those who don't want to do the front weld or something? Your thoughts and/or experience? It brought the question to my mind, if it's simply cut off the old one & weld on the new one, why then is the front pipe attached on some already and not others? Something I'm not aware of or just convenience for install?
Your car should actually use a bolt-on unit that has flanges on both ends, if you want to do an OEM replacement. If you want to use a hi-flow performance cat, they are typically universal and you cut/weld yourself. So the one's you're seeing without the front pipe are probably universals. Also, never believe the photos you see on those websites. They're sometimes of a generic part.
RockAuto.com has OEM bolt-on replacements for ~$200 for your car. That's what I would do. I hate welding exhaust on the car.
RockAuto.com has OEM bolt-on replacements for ~$200 for your car. That's what I would do. I hate welding exhaust on the car.
Mine is welded "but" I forgot to mention, at one point in time the CAT had some sort've repair done to it. Something about cutting a section out or something along those lines? It was partly failed or something to that extent, the shop said instead of outright replacement they could cut a section out or something to that extent? Shortened it so no more bolt-on ability?
So mine may have been bolt-on originally, now it's welded on both ends. So I'll be welding a new one on, which is not that big a deal. In looking at it alignment seems to be the major potential headache.
True on the pictures not always being correct although the ones with the pipe already attached are between $400-500. Straight up walker unit listed for $113, assuming walker is still a trustworthy name. A hi-flo CAT? Assuming the cost is much higher than the walker, which I"d expect, any real benefit behind a stone-stock engine? Not knowing the additional cost, if any, I'd assume it's not worth it on a stock engine.
This is a stone-stock daily driver, no fart can on it or anything like that.
No, there is no benefit but some folks swear by it. On my S2000 when I had a 427 LS1 in it years ago, we tested the hi-flow cats and found that they did not free up any appreciable horsepower compared to "normal" cats; nor did removing the cats altogether. Anyway, a hi-flow cat is typically only a few bucks more than a normal one if you're getting a universal. Just make sure you get the right diameter tubing. Since you're going universal, I recommend Magnaflow. Their hi-flows are $80.
I won't speculate on what has been done to your exhaust and/or cat but it's all moot since you will be welding the new one on yourself. Just be sure that the cat is the problem, and not the O2 sensor.
I won't speculate on what has been done to your exhaust and/or cat but it's all moot since you will be welding the new one on yourself. Just be sure that the cat is the problem, and not the O2 sensor.
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Not sure where you're seeing the cats for $500. Those are probably for the LX which has the cat integral to the exhaust manifold. Like this:
I thought you're referring to one like this, which is what the EX would use:
The latter is about $200 on RockAuto.com. Check out that website, it's your best friend if you like to DIY repairs on your vehicles. Very reputable, tons of inventory, fast shipping, awesome prices...
I thought you're referring to one like this, which is what the EX would use:
The latter is about $200 on RockAuto.com. Check out that website, it's your best friend if you like to DIY repairs on your vehicles. Very reputable, tons of inventory, fast shipping, awesome prices...
Not sure where you're seeing the cats for $500. Those are probably for the LX which has the cat integral to the exhaust manifold. Like this:
I thought you're referring to one like this, which is what the EX would use:
The latter is about $200 on RockAuto.com. Check out that website, it's your best friend if you like to DIY repairs on your vehicles. Very reputable, tons of inventory, fast shipping, awesome prices...
Yes, the lower picture is what I was referring to with having the pipe already connected yet a premium price. As well as wondering what if any difference?
http://www.autozone.com/emission-co...i-vtec-sohc/980063_943870_2149/?checkfit=true
IF I've got the link done right, here's an example off the autozone site. $494 for the same as that pic. If the pipe already attached simply means not doing the front weld, pass on that price I can do the welding myself.
The walker unit for $113 I can get for $20 off. From what you're saying it seems to be the sensible option. I will check out the rockauto site, never had heard of it but I will take a look at it.
Atticus,
I prefer direct fit converters by Magnaflow, Dorman or walker depending on application. However, if you have already modified your converter, why don't you just purchase an oxygen sensor adapter that will make the computer happy. The adapter kit by blackpath is $25 and includes the 90 degree adapter if you need it.
Otherwise, it is as simple as you made it out to be. Chop it and re-weld new part into place. A sawzall makes a nice neat cut and a mig is ideal for welding aluminized pipe used by most manufacturers.
I prefer direct fit converters by Magnaflow, Dorman or walker depending on application. However, if you have already modified your converter, why don't you just purchase an oxygen sensor adapter that will make the computer happy. The adapter kit by blackpath is $25 and includes the 90 degree adapter if you need it.
Otherwise, it is as simple as you made it out to be. Chop it and re-weld new part into place. A sawzall makes a nice neat cut and a mig is ideal for welding aluminized pipe used by most manufacturers.
This... ditch the cat all together and put the spacer in.
U'mm hold up a second, you're way ahead of me already.
1. First off what is a 'direct fit converter' ? Is that what savage 20 posted a pic of, with the pipe attached? Or are you referring to something different?
2. What is an oxygen sensor adapter? IF I'm understanding you correctly this replaces the CAT entirely yet retains whatever sensor is plugged into the CAT now?
3. I am not certain of what repair was done to the CAT, my best understanding is a portion of it was removed in order to restore it to functional status rather than replace it entirely, that was done by a professional shop. It was not something I did as I have no knowledge of such things. This is my first go messing around with the CAT. BTW the CAT on the car is the original, although after this much mileage it had to go poop at some point although what that shop did bought me some time before outright replacement. It did pass a sniffer test after that.
3. The upstream and downstream (correct terms?) 02 sensors in the exhaust were just changed, does this have any impact on putting in an oxygen sensor adapter as you mentioned? They were both failed & have now been replaced.
4. I have a sawzall and intended to use that to make a clean cut, as close to the cat as I can and then clean/remove whatever leftover pipe with a grinder.
5. I don't have mig, I have std arc welding but I can go down to 1/16" rod ( I have that size in 6061 already) which I figured would be easy enough on the pipe without blowing a hole through it. The stock exhaust pipe looks to be regular steel, would I need a specialized welding rod for the aluminizing you mentioned?
If the simplest thing is to get another CAT and weld it in and that makes the system function as it should, that'd be what I'd want to do.
No tweaks on this thing, especially with it's age. It's long in the tooth but still on it's feet & keep it stock seems the wise course but I will allow or defer to your experience.
Ok Atticus,
The converter pictured is a typical direct fit style with an integrated pipe. Usually those require only 1 side to be welded, sometimes neither if it is flanged on both ends.
The oxygen sensor adapter is designed to reduce the sample size of air that the computer is using to determine the converters efficiency. So, a converter with normal flow but poor efficiency can continue to be run on the vehicle without developing a p0420 for "catalyst efficiency below threshold - bank 1". The spacer should be installed on the downstream side of the cat or post converter. Some are located in the middle of the body of the Cat. It threads into the oxygen sensor hole and the sensor threads into it.
As far as a previous repair. I could only see someone "hollowing out" the converter to restore flow to a bad cat in which the substrate has broken up and is choking the motor. Otherwise, a converter is not a serviceable item.
The adapter will work with any properly functioning one(oxygen sensor) so, new or old should not matter.
Lastly, welding aluminized pipe does not require aluminum rods. It is a process that improves corrosion resistance while still being similar to mild steel as far as weld-ability. Also, exhaust systems of vehicles should be welded together while everything is sitting in a neutral position, just as it would on the vehicle. If you attempt to weld a pipe on the ground(makes the over the top weld easy) you will find that even a minor error in the "roll or offset" of a flange or fitting will make re-assembly near impossible later. Which is why I recommend the MIG for welding exhaust.
The converter pictured is a typical direct fit style with an integrated pipe. Usually those require only 1 side to be welded, sometimes neither if it is flanged on both ends.
The oxygen sensor adapter is designed to reduce the sample size of air that the computer is using to determine the converters efficiency. So, a converter with normal flow but poor efficiency can continue to be run on the vehicle without developing a p0420 for "catalyst efficiency below threshold - bank 1". The spacer should be installed on the downstream side of the cat or post converter. Some are located in the middle of the body of the Cat. It threads into the oxygen sensor hole and the sensor threads into it.
As far as a previous repair. I could only see someone "hollowing out" the converter to restore flow to a bad cat in which the substrate has broken up and is choking the motor. Otherwise, a converter is not a serviceable item.
The adapter will work with any properly functioning one(oxygen sensor) so, new or old should not matter.
Lastly, welding aluminized pipe does not require aluminum rods. It is a process that improves corrosion resistance while still being similar to mild steel as far as weld-ability. Also, exhaust systems of vehicles should be welded together while everything is sitting in a neutral position, just as it would on the vehicle. If you attempt to weld a pipe on the ground(makes the over the top weld easy) you will find that even a minor error in the "roll or offset" of a flange or fitting will make re-assembly near impossible later. Which is why I recommend the MIG for welding exhaust.
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Dammit. The yota needs 2 new cats. Uggghhhhhhh
Then, the plugs the toyota tech told me are good to go - ARE NOT!!! This was verified by the Toyota master tech. Bullshit!
Holy crap, that sucks.
Any chance you can modify it, and just go with a single cat?
On a forced induction setup, it is a good idea to change plugs fairly often.
How long ago were the O2S changed? What CEL codes did you have before? And do you have any now? Have you cleared the codes since the O2S replacements?
That's a good question. I'll check into it with the muffler shop.
My first guess to all this troubleshooting was new plugs. So Advanced Auto told me they could get iridium plugs, and I called the Toyota dealership to verify since this is a performance engine (normally I stay away from iridium plugs). I got transferred to a service rep who told me the iridium plugs are good to go.
Before dumping more money into trying to see if different parts would fix it (I'm already in an O2 sensor, fuel filter, plugs, and MAF sensor), I figured it's time to just let it get checked out. I was about to go down the fuel line, but the shop said it's the Cat - saved me money on fuel parts. They also told me I put the wrong the wrong plugs in, which caused me to call Toyota and verify with the master tech.
Now I gotta buy more plugs because the Toyota tech couldn't give me proper instruction about a Toyota truck.
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My first guess to all this troubleshooting was new plugs. So Advanced Auto told me they could get iridium plugs, and I called the Toyota dealership to verify since this is a performance engine (normally I stay away from iridium plugs). I got transferred to a service rep who told me the iridium plugs are good to go.
Before dumping more money into trying to see if different parts would fix it (I'm already in an O2 sensor, fuel filter, plugs, and MAF sensor), I figured it's time to just let it get checked out. I was about to go down the fuel line, but the shop said it's the Cat - saved me money on fuel parts. They also told me I put the wrong the wrong plugs in, which caused me to call Toyota and verify with the master tech.
Now I gotta buy more plugs because the Toyota tech couldn't give me proper instruction about a Toyota truck.
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What plugs did you put in? Do not ever believe a mechanic. The dealer may just be trying to hose you for another set of plugs, because they use a different brand. Also, I prefer iridium plugs for most every vehicle I own.
I stick to Denso and NGK on Japanese vehicles. I also prefer a copper plug when offered, in spite of a platinum one having a much longer service life.
My condolences regarding your dead Cats. That will not be a cheap repair. Maybe time to consider a tune w/cat removal and spacers or emulators.
Since it is supercharged, changing the exhaust back pressure should have little effect on it's ability to make power. Nothing like a turbo that has to wind up.
I bet you have some good options for it if you look around a bit.
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I get that with mom n pop shops, but a dealership??? Cmon. When I was at Freightliner, our techs generally tended to try and be honest.
The plugs I put in WERE NGK at least.
I tend to try and stick to things generally staying stock, mechanically (minus air filters and plugs to a degree). I'll look into the mono cat vs dual cats though. The first thing I want to see is why did they go with dual cats and what difference will a single cat make.
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