Aluminum flecks in ‘07 S4 oil pan. Engine pulled for timing guides & chains.

[srfry]

Engine pulled for timing chain job this week. 1000 miles since oil change. 122k miles on engine. We found a small amount of seemingly non-ferrous metal flakes or specks in the oil. Removed timing covers and see no indication of wear or rub marks. Valve covers removed. Borescope reveals no scarring or other damage to pistons or valves. No apparent damage to cams either. Oil pan not yet removed. What else do we look for? We certainly want to address any issues before re-assembly.

Also, the intake manifold flapper wasn’t functioning but it isn’t seized. Could that possibly be caused by a vacuum leak? Any other ideas?

Codes thrown prior to disassembly: P0300. P0016. P0018. P0421. P0413. P0106.

Thanks all. We much appreciate the forum and support already found.

[Zolli]

I dunno regarding the flakes, but I’ll take a guess - maybe the oil pump? The flecks could be that weird coating they put on gaskets?

The intake manifold flapper is indeed vacuum-actuated, so a leak is a decent possibility, but I imagine you’d hear it. My flapper was stuck enough that the actuator couldn’t move it, but I could by hand. I still took it out and polished it, and it’s right as rain again. Probably worth doing in your case.

[Old_skool]

Also, the intake manifold flapper wasn’t functioning but it isn’t seized. Could that possibly be caused by a vacuum leak? Any other ideas?

With this exact symptom, where you can physically push and turn the spring-loaded arm, but it wont function when driving,
the cause is more often than not a broken diaphram in the actuator (the oval black thing on the left-front of the manifold connected to the spring loaded arm)


First thing to do is try to disconnect the vacuum-tube from the bottom-left of the actuator (if you can wriggle in there)... once its off start the car and put your finger over the end of the tube, if your vacuum system is reasonably good you will feel a definite suction on your fingertip skin as it sit covering the end. Which also mean the actuator is probably toast.

to remove the actuator... 2 x torx screws (which are a pain to remove unless you have a micro-racheting spanner with short torx inserts).
once out you can pry open the tabs around the actuator halves and open it up to visually confirm 100% that the the diaphram has torn and lets air through