The purpose of this post is not to point fingers at any particular brand/seller. But because this involved a critical engine component that can - and has - caused engine damage, I feel that it needs to be shared with everyone.
Recently, there has been a failure of a metal VANOS cover in one of the Malaysia member's E92 M3. Below are the facts:
1. The owner heard a loud whining sound from the engine. Upon investigation, it was determined that the aftermarket metal VANOS covers in Bank 2 (left hand side) had completely disappeared.
2. Somehow, the metal VANOS covers had ground down to a fine metal dust and which was caught by the oil filter. There were no large pieces left. How this is possible I do not know. What I can guess is that the covers had fallen off, been ground down by the timing chain and the resulting dust trapped by the oil filter. There was damage to the oil pump and metal swarf all over the engine. The engine is being rebuilt as we speak (luckily no crank damage).
3. This car had been using the metal VANOS covers for less than 5k kms (3k miles) and had attended two trackdays.
4. At Bank 1, the VANOS covers were still there but had come loose. A few of the clips had loosen sufficiently that the 'hook' was no longer clipped behind the VANOS gear but were sitting on top of the gear. (Pic below is from another car and provided as illustration only)
5. After dismantling the Bank 1 VANOS covers, it was noticed that the hooks from Bank 1 were worn down considerably from a brand new metal VANOS cover from the same seller and batch.
6. This is what a good lock should look like, with the hook fully clipped in behind the VANOS gear.
7. There are quite a large number of E9x M3 in Malaysia using these VANOS covers. News spread quickly about this incident and many owners went to check their cars. Many saw loose clips just by looking through the oil fill hole.
8. One owner opened up his valve covers and saw the below looseness on the VANOS cover clips:
9. [CONJECTURE] I have no proof but the way I see it, the loose clip allowed the aluminum VANOS cover to vibrate/rub against the steel VANOS gear. This wears down the aluminum hook, which makes the VANOS cover even more loose, and rub more. Until eventually the VANOS cover falls off entirely and gets broken/ground up, causing engine damage.
10. Some of these owners reached out to the resellers they bought the covers from and were informed that 1 loose clip is normal and acceptable.
11. Quite a few owners have checked their covers via the oil fill hole and about half of them have seen loose clips.
12. So far there is no correlation on mileage or driving style which may cause the VANOS covers to loosen. Two heavily tracked M3s showed loose covers, as did some very seldom driven, and never driven hard, cars.
13. Myself personally, I am using Slon covers and mine looked ok via the fill hole. As far as I am aware, I am the only one using Slon in my country.
What Should You Do?
Open up your oil fill hole and check that the clips of your metal VANOS covers are fully hooked in. You may need to start and stop the engine several times to see as many clips as possible. (Please remember to put back the oil cap before starting the car).
While this method only allows you to view the Bank 1 VANOS covers it is better than nothing. If you see loose clips then you know you might have them in Bank 2 as well.
To really be sure, you should open up the front timing covers on both banks to inspect the VANOS covers properly.
Again, this post is not meant to fingerpoint to any seller/manufacturer of these metal VANOS covers. The cars in Malaysia use various suppliers of these covers, from both China and the US, and none are immune to this loose clip issue. Half the cars checked have loose clips, half don't.
Another Malaysia owner has tried to share this info in the E9x V8 FB group and was threatened to the point he had to take down the post. Please don't shoot the messenger. We are just trying to share the facts so that other people do not blow up their engines.
I will not be naming names, nor will I be entertaining any PMs on this matter. If you have any questions please ask in this thread and I will answer out in the open for the benefit of all.
Recently, there has been a failure of a metal VANOS cover in one of the Malaysia member's E92 M3. Below are the facts:
1. The owner heard a loud whining sound from the engine. Upon investigation, it was determined that the aftermarket metal VANOS covers in Bank 2 (left hand side) had completely disappeared.
2. Somehow, the metal VANOS covers had ground down to a fine metal dust and which was caught by the oil filter. There were no large pieces left. How this is possible I do not know. What I can guess is that the covers had fallen off, been ground down by the timing chain and the resulting dust trapped by the oil filter. There was damage to the oil pump and metal swarf all over the engine. The engine is being rebuilt as we speak (luckily no crank damage).
3. This car had been using the metal VANOS covers for less than 5k kms (3k miles) and had attended two trackdays.
4. At Bank 1, the VANOS covers were still there but had come loose. A few of the clips had loosen sufficiently that the 'hook' was no longer clipped behind the VANOS gear but were sitting on top of the gear. (Pic below is from another car and provided as illustration only)
5. After dismantling the Bank 1 VANOS covers, it was noticed that the hooks from Bank 1 were worn down considerably from a brand new metal VANOS cover from the same seller and batch.
6. This is what a good lock should look like, with the hook fully clipped in behind the VANOS gear.
7. There are quite a large number of E9x M3 in Malaysia using these VANOS covers. News spread quickly about this incident and many owners went to check their cars. Many saw loose clips just by looking through the oil fill hole.
8. One owner opened up his valve covers and saw the below looseness on the VANOS cover clips:
9. [CONJECTURE] I have no proof but the way I see it, the loose clip allowed the aluminum VANOS cover to vibrate/rub against the steel VANOS gear. This wears down the aluminum hook, which makes the VANOS cover even more loose, and rub more. Until eventually the VANOS cover falls off entirely and gets broken/ground up, causing engine damage.
10. Some of these owners reached out to the resellers they bought the covers from and were informed that 1 loose clip is normal and acceptable.
11. Quite a few owners have checked their covers via the oil fill hole and about half of them have seen loose clips.
12. So far there is no correlation on mileage or driving style which may cause the VANOS covers to loosen. Two heavily tracked M3s showed loose covers, as did some very seldom driven, and never driven hard, cars.
13. Myself personally, I am using Slon covers and mine looked ok via the fill hole. As far as I am aware, I am the only one using Slon in my country.
What Should You Do?
Open up your oil fill hole and check that the clips of your metal VANOS covers are fully hooked in. You may need to start and stop the engine several times to see as many clips as possible. (Please remember to put back the oil cap before starting the car).
While this method only allows you to view the Bank 1 VANOS covers it is better than nothing. If you see loose clips then you know you might have them in Bank 2 as well.
To really be sure, you should open up the front timing covers on both banks to inspect the VANOS covers properly.
Again, this post is not meant to fingerpoint to any seller/manufacturer of these metal VANOS covers. The cars in Malaysia use various suppliers of these covers, from both China and the US, and none are immune to this loose clip issue. Half the cars checked have loose clips, half don't.
Another Malaysia owner has tried to share this info in the E9x V8 FB group and was threatened to the point he had to take down the post. Please don't shoot the messenger. We are just trying to share the facts so that other people do not blow up their engines.
I will not be naming names, nor will I be entertaining any PMs on this matter. If you have any questions please ask in this thread and I will answer out in the open for the benefit of all.
