Hi,

Here is my situation: I have an Audi A4 2.0T 2007. Two weeks ago, low oil pressure light came on when driving the car at cold temperature (-20 deg C). My wife was driving the car and had the good reflexe to stop it beside the road and call me. I went there and checked oil level and it was perfect. I started the car and drove it: no more oil pressure light but I can hear a small unusual sound that possibly come from the engine. So, I stopped the engine and avoid to run it and take a first look at the engine.

I removed oil from the engine and found small metallic particules in the oil filter…not good.

I did search on the internet and found that oil pump failure was something very frequent on modal of Audi close to mine. So, I called an Audi specialist and he was sure that the problem was the oil pump and that the metallic particules inside the oil filter housing was in fact damaged parts from the engine generated by lack of oil flow. He told me that my engine was probably failed. He saw this many times in the last years.

I started to take a look at the engine itself to find the source of particules.

I first removed the head cover to inspect the cam and valves. Visually, everything was in very good shape and no trace of metallic particules at this place. Note that I only did a visual inspection of the head without removing any parts.

I removed the oil pan and checked inside. Very clean and no trace of particules there.

I checked the balance shaft module with the oil pump. The modal of Balance shaft I have on this car is not the one that usually fails. On this type of balance shaft, the oil pump is driven directly by the chain instead of being driven by the end of the second balance shaft. So at this point, the hypothesis of a failed oil pump was not necessarly the first possibility. I inspected also the pickup pipe of the oil pump and it was very clean.

So now, I put back everything in place. Here are the facts:
I do know that oil pressure was not correct when my wife was driving.
I saw metallic particules in the filter housing when I dropped the oil.
I cannot found any metallic particules in the engine and this one turn free when I manually turn it.
The hypothesis that it could be oil pump failure because of the design of the balance shaft module is not longer a possibility because it is a direct gear.

What do you suggest me? From where this metallic particules are coming? Why the oil pressure light came on?

The next step I want to do is to restart the engine again but before I will install a oil pressure jauge with the oil pressure switch and see what is the actual pressure value and see if it is within specs. What do you think?

There is no code stored at all.

David.

 

I don't have any advice for you, and believe those metal parts must have come from something farther inside your engine than you were able to check into. Did you take one of the rod caps off and look at the bearing? That would be another way to see if any damage was done and possibly how long the engine ran without oil pressure. My opinion, if you can still get at the bearing and the shell is damaged, meaning there is copper or scoring on it, don't put it back together, time for a rebuild. If nothing looks bad, I would take a look at the pump. This picture below shows there might be more to it than you'd think.

 

There is a TSB for this issue # 170822 (oil pressure warning with temps below freezing). You will need to either bring it to the dealer or a independent shop that is capable of re flashing the ECM. It is a software issue.
Sucks that you did all that work!

 

Hi Jeff,

Thank you for your reply.

To answer your question, no I did not take off one of the rod caps to see to inspect.

According to me, I had to remove the balance shaft module from there and I decided to not doing it now. But, yes that would be for sure the best thing to do and I will keep that in mind.

Here is few more things I can tell you that make me take this decision:
1- The particules found in the oïl filter housing are very very small.
2- I would have expect to find the same kind of particules in the oïl pan, but nothing was there.
3- 6 months ago, I went to the dealer to replace the High pressure fuel pump, Cam follower and Cam Intake because noise was coming from the back of the engine. We replaced that in a preventive way cause these parts are known to cause a catastrophic failure of the engine. During that work, they found some metallic particles in the oïl. I was thinking that maybe what I see right now may be a rest of that problem and has nothing to do with the actual issue.

What's your feeling about that?

Thanks.
David.

 

Hi M5S5,

This is very interesting. Do you have a document or can you give more détails about this TSB?

Thanks.