Exhaust Manifold Torque Data?

[X5Cat]

I'm finally diving in to replacing both CATS in my 2009 X5 3.0i, for better or worse. Anyone have the recommended torque value for the manifold-to-engine head nuts? The nuts are 11 mm (socket size, not diameter).

While I'm at it, the CAT pipe flange to exhaust pipe flange nuts as well?

Thanks!

[ard]

20Nm for the manifold nuts


Type Thread Tightening specification Torque 1AZ Exhaust system to exhaust manifold N62TU M8 35 ± 2 Nm


2AZ Exhaust system to manifold N52K M10 45 Nm


3AZ Exhaust system to exhaust manifold/ catalytic converter N62TU/ N62 M8 nut 21 Nm


4AZ Clamp, exhaust flap, to tailpipe N62 M6 12 Nm


5AZ Exhaust flap with tailpipe to clamp N62 M6 12 Nm

[X5Cat]

Thanks for the data. I have the N52. Got the CATs in. They're not OEM but thought I'd roll the dice and see how it turns out. Got a problem though in that the two CAT to exhaust flanges are jambed up right next to each other, no space between them, which is not a problem in and of itself, except that the twin exhaust pipes on the vehicle between there and the muffler have maybe 3/4" between them so I can't fit them onto the new CAT flanges to bolt up. Guess I'll have to find a way to squeeze them together, and I'll also probably wind up piling extra flange gaskets on b/c when I squeeze them together, there is a larger gap between one pair of the mating surfaces than there is between the other pair. Darn it.

[X5Cat]

It does have a nice rumble to it, without the muffler system attached, LOL. The wife not happy about it, though. Go figure!

Haven't been able to drive it around yet because of that. I'm anxious to see if the CEL goes off. Wonder how long it will take, if it does. Thoughts on clearing the codes (had the P0430) - good idea or bad?

Thanks

[ard]

Did you replace the cat cause of that code?!?!?!?


If so, SAVE THE OLD CATS.


Often times a cat efficiency code is NOT a bad cat, but rather bat AFRs causing cats to foul


Oh, clearing codes is fine...just jot it down. Do not wait for it to clear, takes WAY too long.

[X5Cat]

Yes, I did replace them because of the code, but more to the point, the poor performance. I am definitely saving the OEM CATs, fully aware that the problem may be something else. I have new A/F and MAF sensors on order. Had already replaced the O2 sensors since they were fairly easy to get to, but problem persisted. Did 2 consecutive treatments with Cataclean, with no effect -- except to my wallet. Picked up these CATS supposedly from Canada at only $168 for the pair, with free shipping. So, I said I'll just give it a shot and maybe either fix it or learn that I need to look for the problem elsewhere. Boy, what a chore, though!

[X5Cat]

Well, got the exhaust flanges lined up and bolted together Thursday night, with the help of a large metal hose clamp and a stubby combination wrench. No apparent exhaust leaks, YAY! Unfortunately, the X runs exactly the same way it did before. CEL still on. I haven't attempted to clear or rerun the codes. I will rerun them, but not expecting to see anything new.

Hats off to those who had said it wasn't the CAT; but, I didn't spend much money, and at least now I know for pretty much sure that I can look elsewhere. Other possible culprits, as I understand it:

1. After-CAT A/F sensors (ordered, arriving early next week)
2. MAF sensor (ordered, arriving early next week) (Ordered the $25 eBay version, will see how that goes. They're $200 - $300 at the parts stores. Absurd!)
3. Vacuum leak - don't hear any, can't find any. So far haven't even found a vacuum hose to plug my gauge into.
4. VANOS - is this the same as "Engine Variable Valve Timing (VVT) Solenoid"? I find it listed at Advance Auto for $135, and $109 with a code. A filter gasket I guess goes with it, I can get for $22. Is this the big solenoid looking thing that sits on top of the engine, kinda in between some of the coils/spark plugs? Anyone know if it as simple as unbolting and remove & replace? Advance has a video showing one all gunked up with metal bits. Maybe I could clean it out, but at that price, I wouldn't mind replacing if it is a fairly direct process.

[X5Cat]

Okay, figured out this VANOS thing, thanks to a couple of youtubes. Dual VANOS units, mounted in the front of the engine. I can see them. Kinda ups the ante $$-wise, since there are 2 of them. I'll see what happens with the new sensors first, and if that doesn't fix things, I'll try just cleaning the VANOS's and reinstalling. I really wouldn't feel bad about paying for 2 of them, if I knew it would solve my problem. One thing I don't see or hear mentioned on the youtubes, though, is the "filter gaskets" for the VANOS. Makes me wonder whether or not that is really a thing.

[ard]

The E39M5 has dual vanos and was legendary for CAT replacements... indeed, BMW put out a service update back in the day to dealers: DO NOT REPLACE CATS FOR CAT CODES.


The issue is that the vanos can cause AFR issues in different parts of the RPM bands- so when you look at idle, its fine...but at 5k it is hosed. The DME keeps compensating, you dont trip long term fuel trim codes, but the cars are getting loaded.


Oh, back in the day, there would be vanos codes...eventually the community learned DONT REPLACE THE VANOS, clean it. BMW would say 'replace it', sometimes under warranty- and after $12k in vanos hardware, including new solenoids, it would fix it. "yep, vanos was bad"


There are TONS of counterfeit MAFs ...they are crap. YMMV. even bosch branded and packaged.


Clean out your vanos solenoids. Take each out, use spray carb cleaner. Flush them hard WHILE ACTUATING THEM. (use 5V I believe, NOT 12! As least on the S62, these are controlled by the DME using regulated voltage. Some use a little 9V battery, which is safe too.) When you get them out, try to actuate them...listen to the sound, you want a nice, crisp snap. I have found they get fouled, oil sludge... then as you are flushing with cleaner the sound changes


Oh, ante wise, buy new orings. Will cost you 2 hours and $20 to clean the solenoids. Im not a betting man, but....

[X5Cat]

Wow, you sound that convinced. Guess I'll have to go clean a pair of VANOS. Thanks. I'd have done it long ago if I'd realized how simple it would be (I think).

Agree that counterfeit parts are a huge problem. I bought some front suspension parts several years back, supposedly MOOG brand. The metal was die stamped MOOG, but it looked like a very generic font and I was suspicious. I actually contacted MOOG directly. Their person's response? "If it says MOOG on it then it's probably real." Whuhhht?