Cold start engine rattle
Hi guys, couple of weeks ago my 2012 Zafira 1.6 started to make a rattle on cold start for couple of seconds, the car is currently on 64k
I decided to do an oil and oil filter change but the problem still persists. The car runs fine otherwise. Attached is a short clip of the rattling sound. Any advice is much appreciated. Thanks in advance.
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Worn Out Member
Diagnostic Kit—Opcom/Vauxcom 200603A,Mongoose Pro GM2 running GDS2 software
Drives a Mineral Black Astra K 1.0 t Sri hatch
I had exactly the same problem with my Zafira B 1.6, with engine A16XER from 2012 and I was finally able to determine the root cause of the problem.
I read a ton of information over the internet, namely:
- Replacing the VVT control gears, actuators and seals, but it did not solved this startup rattling issue.
- Removing the actuator screens, but it did not solved the problem.
- Changing the oil filter housing/cooler, but it did not solved the problem.
- After a oil and filter change, the problem may go away for some time, but it comes back again.
- In some cases, during an oil and filter change, there would be new problems with low oil pressure a lower rpms.
Also, this A16XER engine already uses the new (improved) VVT actuators and gears, and thus the problem should not be the same as the previous Z16XER was having.
In my specific case, all the service which was carried on (once the warranty was expired) was done by me always on due time (DIY entusiast), and thus I knew that I could not have any built up sludge in the VVT actuators/screens.
I always used the correct oil (DEXOS2 spec from reputed manufacturers) and correct premium brand oil filter (MANN-FILTER HU 612/2 x).
Oil pressure control light immediately goes out in the moment the engine starts.
Now, knowing that the symptom is an obvious oil starvation at the VVT system, then the problem must be caused by the oil being drained back into the sump when it should not be.
Keep in mind that this engine uses a cartrige oil filter (and not a spin-on one). So, this means that the oil filter itself has no built in valves (such as the bypass valve). So all the valves are part of the oil filter housing.
If there would be a problem with the anti-drain back valve installed between the oil pump and the oil filter housing, then the oil pressure control light would not go out so fast, as the piping would need to be filled in first, just like in a oil change.
The bypass valve of the oil filter housing plays no role in this case, as it there just in case the filter gets clogged so that the whole engine does not suffer from oil starvation. And the filters that I removed were never in such condition due to regular servicing.
However, there is a 3rd and last valve in the oil filter housing, which is specific to cartridge oil filter types: it’s the drain valve. This valve is responsible for draining the oil from the oil filter housing while the oil filter cap is being unscrewed. The purpose is to let the oil to be drained back into the sump so that you don’t have a mess just like with the spin-on ones. This valve is effectively actuated by the oil filter itself: once you screw the oil filter cap with the oil filter mounted, the bottom part of the oil filter will actually push against this valve and close it.
So, if this valve would be faulty or not pushed properly, then this could justify the initial oil starvation problem.
Therefore, as a preparation to my next steps, I ordered:
1. A OEM oil filter (HENGST FILTER E611H D442), which happens to be the manufacturer of the filter housing as well.
2. A drain valve that I could find on ebay.
And then I did the oil change. Please check the attached picture of what I have found!
As you can see the bottom part of the MANN-FILTER oil filter was heavily bended at the contact point with the drain valve, and thus was letting the oil to flow back to the sump after a few hours of stand still.
I also manually tested the drain valve with my fingers and it felt «OK», with no signs of being broken, twisted or with weak springs. So, I did not replaced it.
Mounted the new filter and immediately I had a differing feeling: filter feels much tighter when inserting if through the central pipe (where the bypass valve is installed); and specially much easier to bolt the filter cap into the filter housing.
After 36 hours of standstill, the engine fires up with absolutely no rattle whatsoever, just like it was brand new. Before, after a few hours the rattle was there.
So, the rattle was effectively caused by the oil filter deforming with time. This conclusion also fits into all the facts that I’ve written above about the symptoms that some other drivers had, specially the ones that said that after some time, the rattle was back.
Also, if you visually compare both filters, you will see that the bottom part of the MANN filter is made of some glue or resine, while with the Hengst filter, it is made of hard plastic. So, this difference in construction causes the rattling problem.
But the main conclusion here is: always use Original or OEM parts. Avoid as much as possible aftermarket parts. In this case, even though MANN-Filter is a reputed premium brand regarding filters, they do not supply original filter to Opel/Vauxhall for this engine. Therefore, they are just an Aftermarket supplier. Hengst on the other hand, is the OEM for this specific filter and thus the filter construction has the same quality as the original, at half of the price.
Please not that I’m not saying that MANN-filter is bad and only Hengst is good, as in fact these two brands are reputaded OEMs for many other filter models (they are only used here as a practical example for this specific situation). What I’m saying that the Original and OEM products will ensure a quality standard that the Aftermarket competition may not be able to offer. And here I quite sure this was the case.
As a side remark, I still use MANN filter for other filter types, as long as they are the OEM of it, and I do like they product quality for those OEM parts. Same thing for Hengst.
I know that if you are not servicing your car by yourself, this may be hard to achieve, but at least now you know that you try to do something about it. In case of doubt, make sure you demand to get the Original filter in use, because it is also not that expensive. And make sure you check that drain valve for any potential damage too, made by the previous non-Original and non-OEM oil filters.