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A job that is remarkably easy to do when the engine is out of the car!

On what to do:

Disconnect the main harness and use a bungee cord to hold it back and out of the way

unplug the hard line brake booster line from the manifold and from the vacuum pump (or tcharge air tube if manual) and leave it loose. you don't want to snap one of those when you pull on things. (yes, I did the first time I did the job)
I learned how brittle those hard lines are when I replaced the check valve. Lucky for me, I only cracked the end, and the new check valve was longer (aftermarket aluminum one).
 

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Wasn't that bad actually. I bought an extra OEM Cat off a co-worker and just held onto it for the last year or so, you know, JUST IN CASE lol. Well, that case came in handy today. $100 for the Cat, and $100 for labor. So, really, not bad at all.
 

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Catalytic converter replacement due to spontaneous failure of DIC.
How did the CAT fail?

Plugged?

Overheated and melted?

What were the driving/running conditions like in order to have the CAT "fail"?

Who told you the CAT had "failed"?

Curious.
.
 

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How did the CAT fail?
Cat failed due to excess fuel being dumped into the exhaust when the DIC gave up. Or it was over a prolonged period of time. However, the car was perfectly fine until the DIC self destructed.


Plugged?


Overheated and melted?
Yes, plugged seemingly instantly, or could be melted material that blocked the piping. Either way, it was severely restricted for exhaust flow.

What were the driving/running conditions like in order to have the CAT "fail"?
Everything was fine, then in an instant, wild bucking, then the car shut off and would not start again.

Who told you the CAT had "failed"?

Curious.
I told me the cat failed (Second time now that I've gone through this). After replacing the DIC, max boost was 3.1 psi and you could hear the turbo leaking through the exhaust side/down pipe flange. Not to mention P0420. Replaced cat, car is 100% back to normal.
 

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Today I did something I've done on just about every car I've owned for the last 15 or so years. Everyone's internet favourite, I took off the MAF and gave it a bit of a clean.

It's one of those jobs that someone like me (amateur to intermediate on the grand spannering scale) can do, beat their chest and reckon they've really done something useful. But it never really makes any difference. It's like fitting a K&N. A sense of achievement but you know deep down you've wasted your time.

BUT....! This genuinely did make a difference! 122k on the car, lots of previous owners, very patchy history but I could immediately feel an improved throttle response and smoother pick up.

Sweet!
 

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Cat failed due to excess fuel being dumped into the exhaust when the DIC gave up. Or it was over a prolonged period of time. However, the car was perfectly fine until the DIC self destructed.




Yes, plugged seemingly instantly, or could be melted material that blocked the piping. Either way, it was severely restricted for exhaust flow.



Everything was fine, then in an instant, wild bucking, then the car shut off and would not start again.



I told me the cat failed (Second time now that I've gone through this). After replacing the DIC, max boost was 3.1 psi and you could hear the turbo leaking through the exhaust side/down pipe flange. Not to mention P0420. Replaced cat, car is 100% back to normal.
This is not a shock. What is surprising is that the cat itself bricked and didn't disintegrate into the muffler with similar results, just farther down the line. Good that you had a spare cat, I have exactly the same thing here prepped and ready, a good low mileage cat and down pipe I bought off a member here, and I believe it was because he switched to a Krona or GS stainless 3 inch stage wtf part.
 

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This is not a shock. What is surprising is that the cat itself bricked and didn't disintegrate into the muffler with similar results, just farther down the line. Good that you had a spare cat, I have exactly the same thing here prepped and ready, a good low mileage cat and down pipe I bought off a member here, and I believe it was because he switched to a Krona or GS stainless 3 inch stage wtf part.
According to the Muffler guy who did the replacement, if I was running lean at the time of failure, the Cat would have disintegrated into a billion little pieces and traveled further back to possibly get caught up in the muffler and bang around like a bunch of marbles.
I was running on the rich side so the fuel basically turned the cat material into concrete at the time of failure. I have an image of the inside of the pipe... It looks like that awful 80's builders paint, not quite white, but not quite grey either. I'll post it when I get home. I believe the inside piping should be black no, or at least dark?
 

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I was running on the rich side so the fuel basically turned the cat material into concrete at the time of failure.
Just asking, I am an 'enthusiastic' driver but rarely push my car to the redline or stress it to a great level (I'll drive all day at 160 kph where I can get away with it but no hot rodding at traffic lights (unless a Volt needs a lesson :cheesy: )) how hard are you driving to cook/fry/meltdown at catalytic converter in a single outing?

Not judging, just wondering.
.
 

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Just asking, I am an 'enthusiastic' driver but rarely push my car to the redline or stress it to a great level (I'll drive all day at 160 kph where I can get away with it but no hot rodding at traffic lights (unless a Volt needs a lesson :cheesy: )) how hard are you driving to cook/fry/meltdown at catalytic converter in a single outing?

Not judging, just wondering.
.
That's the thing, I honestly wasn't. I was just heading home (a 5 minute drive) from the tire shop after getting my ALU-28's (Hammer heads, or Klingons, or whatever people are calling them now lol) put on. I had just made a right turn about 40 seconds before, cruising at 80 km/h (rural road speed limit) and all of a sudden, everything went to $h!t with absolutely no warning. Put in another failing DIC, limped the car home where it stayed parked for a few days until the new DIC arrived. Swapped them out, went to go to work and noticed, no power. Plugged in OBD reader, 3.1 psi of boost and a quite audible turbo coupled with hardly any outward pressure from the muffler exit pipe (you could barely hear any sound from the muffler even at cold start and I have a resonator delete). Next day, P0420.

Apparently, on a turbo car, it really doesn't take much at all and a cat can be fried in an instant due to the pressure from the turbo feeding directly into the exhaust. 3 separate muffler shops told me the same thing.
 

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Drove back in to work and still amazed at the difference cleaning the MAF made. Next on the list is oil, plugs and filters.

In other news, you've got to love a delivery from Sweden ;ol;



 

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According to the Muffler guy who did the replacement, if I was running lean at the time of failure, the Cat would have disintegrated into a billion little pieces and traveled further back to possibly get caught up in the muffler and bang around like a bunch of marbles.
I was running on the rich side so the fuel basically turned the cat material into concrete at the time of failure. I have an image of the inside of the pipe... It looks like that awful 80's builders paint, not quite white, but not quite grey either. I'll post it when I get home. I believe the inside piping should be black no, or at least dark?

 

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Received word form Rockauto that they will be giving me a refund on the previous DIC since I was within the last month of warranty.
Once that refund comes, I'm ordering the NGK DIC.
 

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Thanks for posting your experience of 'pyrolysis' of un-burnt furl from a catastrophic DIC failure. It's pretty graphic! All that hydrocarbon catalytically converted to tar or worse inside the catalyst monolith.

Both of my daughters are driving 9-5's, and I'm grateful that TK3.7 SEM DIC's are designed to throw codes before it gets so far. One brain-dead moment I accidentally installed an old 'emergency' TK3.4 SEM DIC off my shelf, and the car died during my test drive with no CEL. I realized my mistake, swapped in the correct DIC, and that old unit went to scrap immediately. It wasn't worth saving even for a spare if it would do that. I now have a TK3.7 SEM spare for each car - one used and one new.
 

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It was going to be plugs, oil, oil filter, air filter, cabin filter today but a serious miscalculation re: the trolley jack and axle stands I can get under my 9-3 and what I can get under the 9-5 meant the oil and filter will have to wait for another day! Couldn't even get the ramps under.

Anyway, plugs and air filter were both pretty bad. Forgot to get a pic of the cabin filter but I'm surprised we haven't all got Ebola.




I had no intention of doing but pretty solid evidence for not taking the sellers word for it re: maintenance.

Another word of warning for you crazy kids. I couldn't get the car high enough on the trolley jack just jacking the front centre. Started to try some sort of workaround with the side jacking points, the trolley and a pair of axle stands. Then I took a deep breath and stopped what I was doing. I know I wanted to get everything done today but the thought of dying alone on a deserted industrial estate under 2 tonnes of Saab wasn't how I saw myself going.

There's a guy down the road who rents out lift time. I'll use that.
 

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Ordered up an NGK DIC and NGK PFR6H-10 plugs to go with it. Not taking ANY chances ever again.
Rockauto now has 3 NGK DIC's left by the way.
 
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