E70 X5 Catalytic Converter Replacement Bank 1
 

My cat melted as a result of a really bad misfire that caused the inner workings (I can hear noise from the cat) to deteriorate. CEL p0420 Bank 1. So I need a front cat. Suffered a massive misfire while on my way home. I was close to my house so I drove it home. Took around 5-8 minutes. When I got home, the cat was glowing red. Indeed it was toast.


These are the parts I used.

Are you replacing with an OE cat? Doenst look like cutting involved. Get it up in the air and start taking parts off!

:)

How long did it take that 'bad misfire' to kill your cat????

I was driving home and the horrible misfire started. I was around 5 minutes away from my house so I drove her home. The crankcase vent was making a high pitched whistle. I ended up replacing the valve cover, gaskets, breather hose, sparkplug seals, OFH gasket, oil cooler gasket, ignition coils, spark plugs, replaced the flange on a thermostat hose (# 11537541992) that started leaking after removal with a Reins aluminum flange. (# CHC0609) Also cleaned out the crankcase with seafoam spray and did a hot oil change w/ fresh Mann filter. Used all OEM parts except for the hose flange which is OE. I think I should be good with maintenance for a while ;)

I'm going to attempt to replace the cat on friday. I got a Aftermarket direct fit part. OEM is too pricey at the moment, plus I'm going to do a muffler delete right after I get the new cat in. Looking to beef up the sound and put in some 4' Magnaflow exhaust tips. :cool:

lol do you understand OE vs OEM?

:rofl: yes. I got OE style, direct fit. It's not OE or OEM, but it should last the life of the vehicle and fit without modifications.

Oh. You bought a aftermarket part- neither OE nor OEM.


"OE style" means nothing- Seriously it means whatever the seller wants it to mean.



When you get it done, successfully, post back what you bought and how it went....

[QUOTE=ard;1156841]Oh. You bought a aftermarket part- neither OE nor OEM.


"OE style" means nothing- Seriously it means whatever the seller wants it to mean.



When you get it done, successfully, post back what you bought and how it went....

That's correct, it's definitely aftermarket but looks solid. Hoping I can get to it without too much of a hassle. I'll post pics when I'm done.

A short term misfire shouldn’t kill a cat. I’m skeptical that’s your issue. I’ve also not really heard of cats making noise, but maybe so.

I was trying to get at that above..a 5 minute misfire?


Cats can break up and rattle.


If he is replacing this only based on 'cat codes', you want to make 1000% sure it isnt something else driving the issue.


Save that old cat after you finish....

Thing was as red as the devil, probably redder when I opened the hood. Could of been past 5 minutes give or take. It was stalling really bad, I barely made it home. Rode like I was on 2 cylinders :rofl:

I will, but I'm 100% its the cat. Sounded like it was melting, I could hear all of the internal parts breaking apart when It was cooling down. I try to install new cat tomorrow.

While cooling down, there is often a lot of cracking, popping, rattling, ticking, etc. It's a natural occurrence. Being that it was as hot as you mention, it was probably quite loud as it was cooling down.

I'm confused as to how you can hear the cat making noise now. There are no moving parts and not really any noise to be heard in operation. If you removed it and the cells had broken down, you would hear them as you shook the cat but if you had removed it already, you wouldn't have to ask how hard of a DIY it is. You'd already know.

Just because it was glowing red or orange doesn't mean it's dead. They operate at high temperatures anyway and at highway speeds, will attain very high temperatures, especially under load, even to the point of incandescence.

Also, is the catalytic converter visible under the hood? I thought it was further under the vehicle in which case I question what you saw under the hood glowing orange or red.

Like others, I suggest moving forward with caution and a bit of diagnostic common sense. Otherwise, if you just want an answer to your question, I think one has been provided already. Good luck.

Was able to remove the cat, but not from the engine bay. Let me say this isn't a easy job, I'm beat :bawling:,and just as I suspected the cat no esta bueno. Honeycomb came out in pieces and looks melted in various spots. Safe to say it is burned toast. Tomorrow I will continue and see what I have to do to complete the job.

If it got red hot then it’s clogged and yes it’s toast. And ard is right at that point they can break up and make noise. That’s usually caused by a rich condition over and extended period of time though, failing O2 sensors can cause that. While it may have officially died during your VCG misfire, I still don’t think the short term misfire was the primary cause

[QUOTE=absentmathis;1157027]If it got red hot then it’s clogged and yes it’s toast. And ard is right at that point they can break up and make noise. That’s usually caused by a rich condition over and extended period of time though, failing O2 sensors can cause that. While it may have officially died during your VCG misfire, I still don’t think the short term misfire was the primary cause[/

I'm guessing it was a mixture different things, the valve cover, ignition coils fouled up plugs, air leak. I replaced a good amount of parts and she's running great except the cat issue. Ran her through ISTA and the cat is the only issue I'm having. I need to get this done, I have emissions testing before the end of the month. :nervous:

Agree exhaust system can make noise under normal cooling condition, esp after spirited drive. But red hot cat isn’t typical, and when toasted can break and rattle. Re: visibility, can’t say for certain on all models, but they’re in the downpipe on at least some models.

[QUOTE=BMWX5CHI;1157028]

Why don’t just empty the cat and use fouler to insert the post cat o2 sensor?


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[QUOTE=Dr.M.Kassab;1157080]Aside from the main point that I care about the planet that my kids live on, most BMWs I’ve heard with no cats don’t sound great. My first attempt was way back when my old e36 cat got clogged and turned red hot.

[QUOTE=josiahg52;1156936]While cooling down, there is often a lot of cracking, popping, rattling, ticking, etc. It's a natural occurrence. Being that it was as hot as you mention, it was probably quite loud as it was cooling down.

If you take a good look you can see a the front cat pretty good, the rear is a bit more hidden but still somewhat visible.

So I finally finished up replacing the front cat. PITA!!!! but doable. You will need a nice arsonal of tools. According to the BMW e70 service manual, you have to remove the rear cat first to get to the front cat and to remove the rear cat you need to take out the entire exhaust. :hitanykey: I didn't do it this way.

Here are the step I used. If you have a lift it will definitely save you the headaches and muscle pain from moving around. I used 2 jack stand at the jack points. Remove both o2 sensors from the cat. I sprayed the nuts at the flange of the cat and let them soak a bit. With a good few whacks from a hammer and a good socket set, I was able to remove both nuts with no issues. Looks like the bolts are welded in place so there is no way to remove the cat even if you remove all the nuts. Cutting it out was my only option. Used a Dewalt low profile sawzall and a new bimetal blade. There no room for errors so I was careful not to ding or cut anything near. I cut as high as I could to shorting the pipe so I could pull it out from the engine easier. (wish that was true) After cutting I removed the 8 nuts holding the cat into place to the manifold. I was able to pull it out with some maneuvering. You have to wiggle and jiggle and move it around as needed. Not fun at all.

Here's all the crap that was moving around. You can see a nice huge that fell out. It was definitely on fire and melting at one point. I made sure to suck up all of the debris from the resonator flange. Used my wet/dry vac and stuffed a rag in the left exhaust tip to help create more suction. I was able to suck everything out. Shaking and whacking the resonator pipe with a soft rubber hammer helped make sure everything got sucked up

Now comes the fun part. I tried to insert the new cat through the top of the engine. There's not enough room. After figuring out that there's no way it's going to fit i like this, I took a break. I needed a bit more space to the left of me which is where the ABS module sits, so I decided to pull it out. It's held in place by 1 10mm bolt and some rubber fittings. I unscrewed the brake lines carefully with a wrench. I used a pry bar to help it loose from the rubber fittings. Finally I was able to pull it out. You will lose a lot of brake fluid, so I need to refill and bleed the ABS system out. Now there's enough room to insert the new cat through the top. I used a cloth to gently pull the brake lines out the way while I was inserting the new cat.

Now it's time to insert the new cat. I was able to push it in through the open space now that the ABS module has been removed. So I inserted it to the left of the AC hose right were the ABS box sits. Lots of maneuvering is needed to get it to slip through. The new cat had some sort of bracket welded to it close to the flange. I cut it off, there's no need for it. It would have made it impossible to get it in with it attached. The aluminum sleeve on the AC hose took a beating. (oh well lol) I hate how its always in the way of everything. Finally got the cat in and ready to test fit. I'm beat and my body hurts lmao.

Man that looks brutal...


One comment...you MAY have a tough time bleeding that ABS unit. Getting every little bit of air out of all the circuits can be a bear. You need to actuate the ABS pump AND flush vigorously and repeatedly to get little bubbles out. I had an incident w my M5 (blew out a brakeline, drove 150 miles home and emptied the system) where I couldnt get a decent pedal feel. Finally gave it to a buddy at the dealer- took him 3 goes.


You cat sure looked bad. Gotta imagine something was going wrong for quite some time. Hope the new one does the trick

I'm going to run ITSA or INPA to activate the ABS module and bleed all 4 corners, hoping it will do the job.

Nice work. I bet the thing is running well after all the recent work.

Where did you get the replacement cat(s)? Dealer? ECS Tuning? There's a place in TX that sells replacement assemblies for less than $500 ea. Not sure if anyone has used them; but gotta be better than $1200+ each for OEM remans... Especially on a $7-8000 car...:dunno: https://www.discountconverter.com/di...&CylSelected=6

I got it off a eBay seller I've purchased from in the past. Good quality. Looks like it was made in Canada and welded together in the US.

Definitely, she's running great :thumbup: