After replacing a blown out crank shaft seal on my 1999 A6 Quattro 2.8, and taking the advice of Oldmots, today I took apart my PCV system in order to inspect it thoroughly for any blockages that could have caused the seal to blow out in the first place. Very crudy, and in need of replacement, but none of the hoses, nor the PCV valve contained any blockages. However, there is a possible block in the PCV suction pump. By possible, I mean that I do not know enough about how the suction pump is supposed to operate in order to determine whether or not it is functioning properly.

Here is a picture of the suction pump, as well as a description of how I see it functioning:




As you can see, the pump allows airflow from the top valve of the pump to the bottom valve (denoted by the green arrow), although it does not allow airflow the opposite way (assumedly a blow back preventer, which makes sense). However, as seen by the red markings, I cannot seem to get airflow at all through the side valve, whether it be through the top valve or the bottom valve. I am guessing (kind of hoping, in fact) that this is abnormal and needs replacing, as I have read on a few websites that clogged suction pumps often result in crankshaft seal leaks. Anyone here who has detailed knowledge of how these are supposed to function?

Thanks!

 

I'd suggest you look into replacing your oil cap with ventilated one!

Any type of crankcase ventilation on any Audi is proven to be troublesome. Humidity an low temperatures are best conditions for failures. Check with your local dealer about the correct pump application - pumps, spyder pipes are known to be climate specific.

FSI gunk - Google it!

 

Thanks for the info. I went ahead and replaced my PCV system entirely (minus one hose that I just can't seem to get to, but it's not recommended to be changed anyways). Was a pretty simple DIY, minus the "one-use-clamps-of-death" (why the hell do people still use those things?!?!) As for the ventilated oil cap, I contacted an Audi Authorized Dealer in Colorado and asked their parts department about it, but he claimed he had never heard of such a thing; most likely, he's ill-informed. I'll do some searching about it, but if anyone has a link as to where to buy this type of cap, that'd be a big help.

Thanks!

 

Pressure relief OIL CAP

 

Excellent, I shall be purchasing that. I live in Colorado, and I could just see that tiny y-valve on the suction pump getting frozen during the winter, and having another incident like I just had.

Thanks for the link!