So, long story short, I incorrectly changed my spark plugs, truck misfired but still drove, and needing to get to school I stupidly drove it anyway. Problem is, once when I got home I noticed a noise from under the truck. I checked it out and saw that the first catalytic converter was red hot. I knew this was bad and if the materials in the catalytic converter get screwed up, then it will be an expensive repair. The problem is, after I fixed the misfiring and started driving the truck again, it is having some weird symptoms.

Now I am 99% positive it is a problem with the cat. The truck runs fine up until around 60mph. I am convinced that it is backpressure from the busted catalytic converter that is causing the truck to not accelerate past that. Even acceleration from 0-30 takes forever but it's still drivable. Anywho, my question is, what are some signs of a bad catalytic converter?

The one cat that was red hot doesn't actually seem to be my problem, my problem seems (to me) to be from the last catalytic converter. Once I'm done driving I can peak my head under the truck and hear noises coming specifically from that one cat that sound like breaking glass and sizzling and everything. It's weird but I believe that the last cat is my problem and not the first one that got red hot. Am I correct in assuming this?

So, my final solution is to cut out the last cat and straight-pipe that section. If the truck runs a lot better, then I know it was that cat and I shouldn't have a CEL problem considering that there isn't an 02 sensor after the last cat, correct? I would prefer not to have a discussion about global warming and how removing a cat is not only illegal but harmful and everything. I know this, I am a 16 year old kid short on money and I plan on replacing it sometime soon. This is more of a temporary fix.

Basically:
1. What are the symptoms of a busted cat?
2. Will I get a CEL for straight-piping the last cat?
3. Which cat do you guys think is the problem?

Thanks a bunch in advance. You guys are always great.

 

You loaded them both down with fuel. It may come out of it eventually, as long as the truck doesn't have a misfire anymore. It'll take time to burn that out of the cat. You'd have to drive for an extended amount of time to get the cat warmed up properly and keep it at that temp for quite a while. If you need to buy another one then I'd look at buying one from a junkyard or a highflow cat from Magnaflow.

Also, one is a resonator and one is the cat.


GB :)

 

you could also try running a fuel booster ie octane booster/ injector cleaner since these do cause a slight increase in exhaust gas tempuature that would help clean the cat i agree with bird 76mojo i think you loaded it down with excess fuel i would try that for a few fill up and see what happens

i hate you people in outside of california since junkyards cant legaly sell cats here we are stuck going oem freakign expensive

 

^^I doubt that would help any...

Unless you have strict emissions where you live, just punch out the last cat and see what happens.

 

yeah just cut out the cat, hollow it out, run strait pipe though it, tack it onto the strait pipe ( were covered by the heat shield, unless you just want to make a nice pretty bead around the whole thing) then if you don't have emissions or very strict emissions then it will pass the visual and you won't have to worry about your cat giving you issues, and yes a cloged up cat can cause poor acceleration, and i imagine if it got red hot the metals inside would all melt if the steel around it was that hot, so most likely i would imagin its srewed up permanatly form it.

 

or he can just do what everyone else does and just punch it out with a screwdriver, and not deal with welding a new piece in there... lol

 

Well, I've already run like 3 full tanks worth of gas through the truck. Do you think it would take more than that? Would the cat overloaded with fuel explain the fact that I'm not getting a CEL? I have one cat-looking thing that is mounted sideways and is smaller. Then I have two larger ones that are mounted aiming towards the back of the truck. If the smaller one is the resonator, couldn't I just cut that out too? That's the thing that got red hot after the misfiring which is fixed now. My truck just feels like "I chopped the ***** off of it", for lack of a better description.

I could try that if you think it takes more than 3 full tanks of gas to clean out those cats. Haha yeah, Cali is pretty bad. CT isn't too bad, plus my truck isn't due for emissions until 2013 and by then I plan on living in Northern Maine where there are no emission tests. I almost had a heart attack at the age of 16 when I saw the dealer price in CT for a new cat was $1800.

That's the plan man. Just so you guys know, its symptoms are: terrible acceleration (especially under load, i.e. uphills, towing, etc.), "coughing" from the intake area, crackling noise coming from the last cat, and louder than normal exhaust noise.

Yeah, that's what I was really thinking about doing.

 

Don't cats have a 80K warranty on them? I can't remember the year term though.

My mom lucked out on her Audi and got a bad cat replaced under warranty at 79,??? miles. $1000 savings :)

 

I just looked it up, the warranty is 8 years/ 80,000 miles. Whichever is first, and unfortunately, my truck is 9 years old now.

 

ya, and warranties dont cover damage caused from doing something stupid...

 

So true... lol

 

cats are probly bad if you let them get hot enough to glow red. this is probly whats causing your slugish performance.

if you punch out the last cat it wont cause any issues with a cel because there is nothing after it. you can just unhook your exhaust there and punch it out... tho a screw driver will not do it. it takes some pretty mighty force and i used a big bar with a large point. once you have beat on it for a while start the vehicle (not in a garage, outdoors) and rev it a few time and not the big cloud of crap that comes out. re install exhaust and your done.

 

That's what I thought and my last cat is the one that is making all kinds of noise at idle and everything so I figure I'll just punch that one out. One of my buddies told me to use a cat's paw and a hammer.

 

If you've already run 3 tanks through it and it hasn't gotten any better then I'd say you're in for some repair work. In the future don't ever do this again. Not just because of the cats but it is possible to "wash" a cylinder with fuel until it no longer has the same compression numbers (worn rings) that the rest have = engine rebuild.

Stay WELL AWAY when you start it and blow the powder/ceramics out of it. Deadly **** in there..


GB :)

 

Do you really think I could have done that just from this experience alone? I mean I did drive it to school and back about 3 times while it was misfiring so that could possibly explain a lot.

Yeah, I figured that the paladium and stuff is dangerous so I'll be very far away.

 

FYI you can get aftermarket cats at O'Reilly's for around $200. I've used one before with no problems.

 

I seriously doubt you washed the cylinder down to the point where it no longer has adequate compression but it is possible. Every engine takes a different amount of time for this to happen.


How far is your school away from you?


I imagine it's just a plugged cat. Look on Ebay for magnaflow cats. There used to be some really nice deals on there, although it would take a fab shop to make it fit properly. You're probably better off getting an OEM cat either new or from a junkyard.



GB :)

 

Yeah, that's what I'm going to end up doing if it turns out it's one of the first 2 cats that is the problem.

I live a maximum of 4 miles from my school so I probably drove less than 20 miles altogether. I really hope it's a plugged cat, preferably the last cat because then I can just straight-pipe it instead of replacing it, but if it's not the last cat, then I think magnaflow would be the way to go. I am considering getting a magnaflow cat-back system and muffler anyways...

Thanks for all of the replies by the way guys. These forums are freakin' awesome!

 

Quick question - what was causing the misfire??



GB :)

 

Haha, me being stupid and not replacing one plug wire at a time and taking them all off because I thought it would save time. Basically, I screwed up which wires go to which cylinder, which caused the misfire. It was a combination of that and a cracked spark plug. The truck still drove though, roughly, but it still got me from home to school and back.

 

well stephen i like to do mine right and if you just knock every thing out with a screw driver you still have the back pressure and it would just create resonounce chamber and probably sound gay

 

I've cleaned out a few cats in my day and we always used a steel rod and a hammer. You just have to poke and prod around in there a little. It's not that hard to get it all out. It's not like it's glued in. It's just a formed chunk of media (mystery materials lol) that the canister is stamped to hold onto tightly. Once you fracture it, the pieces come out easily enough.



GB :)

 

yeha i'm just saying when my friend did it like that to his car it sounded kinda retarded, and then he did what I said and it stoped sounding gay, me i din't bother cause i don't need emmissions where i'm from and my mechanic dosent give a **** when it comes to visual inspection so it didn't matter one bit for me, but my friends car was also a smaller four cylinder too so that might of had somthing to do with it

 

So I cut the muffler side of the last cat and unfortunately, this is what i found.


I believe there are 4 cats on this truck but that sounds just plain stupid so would somebody please correct me?!
1:
2:
3:
4:

3 is the one that got red hot. Is this even a cat or is it a resignator? Could a resignator get clogged and cause my issues?!

 

can you take some better pictures? those dont really show much. try having someone hold a flashlight and holding the camera a little steadier.