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2007 S8 V10 Oil filter horror & blocked oil pick up screen @ 85000 km
2 weeks ago I went into town & drove the car pretty warm. Parked it bought some parts & tools and car started but stalled after 20 seconds the moment I turned my wheel. Tried a few times starting. Engine picked up but stopped after a few seconds. Decided to do the rest of my shoppings by foot and come back after an hours. Tried starting again and engine picked up and didn't stall at all.
Drove to several spots did my things but gave car enough time to cool down and started every time fine and drove without a problem back home. Back home I decided to test. 5 minutes after I had stopped the car I restarted and yest there did it again after a 30 seconds engine stalled again.
After I read a lot, in all the related topics I could find that the PCV should go straight on the top of my suspect list. Also the fuel pump or engine crank sensor.
I only found a minor oil leak coming from the top back of the engine behind the PCV from it's worn orange o-ring. Reading the car with Rosstech cable couldn't find any new codes I already didn't had in 2014 when I bought the car, I could hear a high pitch whining sound coming from the area where the PCV is located next to the oil filter.
I decided that PCV, still the original one with a green paint mark on it, needed to be replaced.
When I take the oil cap off the engine generates a huge vacuum sucking on the lid opening and the whining sound stopped.
So almost seemed like the PCV especially noting the sound comes from that region.
Anyway I ordered an OEM PCV 079103464D + intake spacers to keep the head coool + oil separator heater bypass kit from JHMMotorsports.
Original PCV, dirt inside oil outlet pipe is from mud and sand after it fell onto the ground ;-)
Unfortunately when the goods received it worked out they send me the wrong PCV from a V8 instead of a V10.
From the outside it looks the same only the small oil outlet pipe on the bottom directs into another direction and interferes with a metal fuel line. In no way I could adapt it to make it fit.
So after getting in touch with the company and getting a conformation they going to get the right 079103464D to me. New PCV but wrong part number see angle oil outlet pipe
Then I decided to pull the lid on the oil filter housing. It was a first for me to find the oil filter on top of the engine in the back. Always used to a steel oil filter cylinder underneath the engine.
Anyway I got a 32mm and opening up the lid and to my disgrace I pulled out the following
Could this be the reason for the unusual sound and or extreme vacuum? Blowing inside the 2 PCV valves and closing one of the 2 outlet ports they both let air pass easily through.
I put both PCV on a scale and measured around 14 grams more weight in the original old one compared to the new one. Sure I can't compare that as there could be a slight difference as they both 2 different partnumbers. 079103464D vs 079103464F
But maybe the the weight difference carbon build up or some oil left on the inside.
new PCV weight old PCV weight
I tried searching for information about an oil bypass valve for the V10 filter system but can't find any documentation. The conventional filters have a build in bypass valve but this filter doesn't seem to have that. Isn't that dangerous for the engine or is the filter just located into a side track and gets the whole engine at all times the full oil pressure?
It scarred me to pull such a filter out but maybe it's normal and every closed filter cylinder end's up with the same on the inside but we never see it. The way it is clogged up and the weight of black tar seal likewise stuff hanging from it is astonishing. I am now getting worried about the Japanese oil filter change procedure. Bought the car with only 75k km from Japan replaced the oil without the filter and now 4 years later at around 84k km.
Anyway new filter is on it's way from the dealer and hopefully JHM is sending me soon the right PCV valve.
I am going to vacuum suck some of the oil out of the car and see what crap comes up from the bottom of the engine.
Hope the problems with stalling engine when hot where related to these problems.
Last edited by -Treser-; 10-26-2018 at 06:23 AM.
Reason: cleaning up make it better readable
Wow....I would say you have something fishing going on there.
Did I read it right where you state you bought the car with 75KM on the clock, you changed the oil and not the filter and that filter is STILL in the car (actually it's the one you removed) and it's FOUR years later and another 9KM on the car?
If so, that's the first thing I would do is to change the oil and filter. I would save a sample of the oil in case you want to get it sent out for oil analysis. I would heat the car up good and do another oil change in a very short period of time from the bottom of the car to drain anything out.
That filter is NOT what is supposed to look like. It should just look like a regular oil filter that's been in service, with no sludge:
Here is an oil change procedure I put together. As I mentioned, do another oil and filter change after a few hundred KM's and drain it from the bottom. I bet your issue has a very good chance of going away.
Yes Paul found your post a week ago when searching for more info relating the unknown round lid next to the PCV. Your post was just the missing information I needed to follow trough and open it up. I admit not the best move that I didn't trace it down earlier. Should probably have done it right after I bought the car in 2015, I just checked my paperwork and in late 2014 I started the negotiations with the car dealer. The dealer drove the car for 5450 km before selling it to me. During that period they brought the car ones to an Auckland German car specialist and received the following invoice.
This is the only invoice or any car history paperwork I received with the car. Other paperwork that came with the car was related to the border check and import paperwork + lots of the Japanese paperwork and service books and manuals.
They replaced 3 ground cables and wrote the comment "when driving with low fuel the car misfires, fault mass airflow sensor, fault throttle control valve, fault ecu"
For the record when I bought the car and since there never came any fault codes up that relate in anyway to above remarks. The only thing that changed from the moment I got my hands on the car was that I reconnected the vacuum line at the Kreissegg exhaust valves and let it breath as intended when modified. With closed valves it can happen that collected water clogged up the bottom of the end mufflers and blocked the small opening when in closed valve setting. Car wouldn't start. Had this ones happen to me when I drove the car with closed exhausts valves for a couple of weeks. I am not sure what their comment meant "when driving with low fuel the car misfires"
Low as in low level in the petrol tank or low as in low octane?
I remember when I first time opened the oil cap it had some sludge around the edges of the oil fill gap. I just checked my service notice board in the workshop and last new Castrol titanium oil 5W30 change was at 03-2017.
To get the most of this gunk out of the engine do I best first heat up the engine without the new clean filter and then stall & let run it empty from the bottom to get as much as possible dirt moving and hopefully disappearing via the bottom hole. I am afraid there is so much sludge in there that it will clog up the new filter.
Since the existing oil isn't that old I probably can let it sit outside the car & poor it over to shift the solids and fill it again up into the car and repeat the whole heating up and dumping it from the bottom. In that way I every time take some of the possible sludge out that is sticking behind corners. After I have done that a couple of times I fill up the new oil and filter and then drive it for 500 km and replace oil again? Not sure if this is the best method when this much sludge but just try to imagine how to best approach this.
Do I maybe need to get one of these products you can buy to flush and clean your oil system from sludge?
Are these products safe? Don't they damage seals and gaskets?
Or is there a chance, when I bring too much of the old settled dirt into moving, this will clog up some narrow passages and create new bigger problems?
Curious what your thought are for getting this extraordinary load of sludge out of an engine.
ScottCNelson that price is very tempting but I like to stay with OEM for such an important component.
Also I already bought one from JMHMotorsports.
Last edited by -Treser-; 10-24-2018 at 08:30 PM.
Reason: cleaning up make it better readable
Yes Paul I read your post a week ago when searching for more info relating that unknown round lid next to the PCV. Your post was just the missing information I needed to follow trough and open it up. I admit not the best move that I didn't traced the oil filter earlier. Should have done it after I bought the car in 2015, I just checked my paperwork and in late 2014 I started the negotiations with the car dealer. Going trough the history of the car the dealer drove the car for 5450 km before selling it to me. During that period they brought the car ones to an Auckland German car specialist and received the following invoice.
This is the only invoice or any car history paperwork I received with the car. Other paperwork is related to the border check and import paperwork + lots of Japanese paperwork and service books and manuals.
They replaced 3 ground cables and wrote the comment "when driving with low fuel the car misfires, fault mass airflow sensor, fault throttle control valve, fault ecu"
For the record when I bought the car and since there never came any fault codes up that relate in anyway to above remarks. The only thing that changed from the moment I got my hands on the car was that I reconnected the vacuum line at the Kreissegg exhaust valves and that let breath the car as intended. With closed valves it can happen that collected water clogged up the bottom of the end mufflers and blocked the small opening when in closed valve setting. Car wouldn't start. Had this ones happen to me when I drove the car with closed exhausts valves for a couple of weeks. After I figured it out and drove the car up a hill a whole load of condensation ran out of the exhaust. I am not sure what their comment meant "when driving with low fuel the car misfires"
Low as in low level in the petrol tank or low as in low octane?
I remember when I opened the first time the oil cap it had some sludge around the edges of the oil fill gap. I just checked my service notice board in the workshop and last new oil 5W30 change was at 03-2017.
To get the most of this gunk out of the engine do I best first heat up the engine without the new clean filter and then let it run empty from the bottom to get as much as possible dirt moving and hopefully disappearing via the bottom hole. I am afraid there is so much sludge in there that it will clog up the new filter.
Since the existing oil isn't that old I probably can let it sit outside the car & poor it over to shift the solids and fill it again up into the car and repeat the whole heating up and dumping it from the bottom. In that way I every time take some of the possible sludge out that is sticking behind corners. After I have done that a couple of times I fill up the new oil and filter and then drive it for 500 km and replace oil again? Not sure if this is the best method when this much sludge but just try to imagine how to best approach this.
Do I maybe need to get one of these products you can buy to flush and clean your oil system from sludge?
Are these products safe? Don't they damage seals and gaskets..
Or is there a chance when I bring too much of the old settled dirt into moving this could clog up something and create new problems?
Curious what your thought are for getting such an extraordinary load of sludge out an engine.
Luckily I've got all the time and not relying on it.
ScottCNelson that price is very tempting but I like to stay with OEM for such an important component.
Also I already bought one from JMHMotorsports only received the wrong one so now have to wait and see when the right one arrives.
Never run a car while draining the oil, even a few seconds of running without oil is REALLY bad.
I personally would change the oil and filter with Mobil 0W-40 European Formula if it available to you, drive it a few days and do another oil/filter change and see what you find. And cut the filter open and inspect it for any debris.
I think this will solve 99% of your problem. Do you know how much pressure drop there was across that filter? A huge amount.
Then I would change the oil/filter in 3-4000 KM and see what you find.
Yea, it's going to cost you a few dollars to buy the materials, but think of how much you have saved on filters so far! Don't put the old oil back in there.
Yes exactly Paul I was thinking on changing from Castrol Full synthetic 5W-30 to 0W-40. Was always a bit wary about using such a thin oil but now after seeing the sludge that can form inside a engine and the risks of oil to thick passing the narrowed passages I rethink that opinion and might indeed best used the thinnest oil available. Luckily the engine doesn't show any leaks besides the minor one around the PCV o-ring and it maybe could be safe to switch back to such a thin oil.
IYou sure I can't do the flush and first oil warming & circulating without the filter installed? I am not going to drive it just follow the whole procedure from the ramp in idle.
I am aware the pressure drop must be huge with such a clogged up filter. Especially knowing the V10 engine is already constructed with an extreme low oil pressure.
Yes I don't put the old oil back in the engine to drive but just to cycle a few times more the whole process of letting it idle warm when positioned on the ramps and then repeat the whole flushing process.
May I ad after reading a bit more into engine flush I found the following interesting comment in our New Zealand AA forum:
"By ABayliss AA Expert 2195 Posts 30 March 2015 at 10:17am Engine flushing is fine if the engine isn't "sludged". This term refers to the oil throughout the engine becoming contaminated with carbon deposits and sticking to internal engine component surfaces, becoming as hard as concrete. Basically, an engine that is badly sludged is usually the result of a lack of servicing, a problem that has been associated with some Japanese Imports. When an engine gets to this stage, the only real fix is to completely dismantle the engine and thoroughly clean all the deposits, but as you can appreciate, this is not an economically viable thing to do on a 20 year old vehicle.
The horror stories you've heard about flushing are when the sludged deposits are flushed loose, going through the oil galeries and rapidly wearing the engine (like grit mixing with the oil). So it's not the flushing process which causes the problem - that was a pre-existing problem which the flushing process found out. A sludged engine will eventually fail by itself, without flushing - just that it may last a little longer.
So, to answer your question, flushing the engine and running diesel oil for a period could be a good solution, and probably worth a try, but if the engine is badly sludged, it may cause problems sooner than if left alone."
I am still checking Youtube movies about seafoam and ATF cleaning technique and a little bit wary about such for our delicate Audi's. See a lot about smoke coming from the exhausts and creating black tail pipes. More blow-by. Doesn't sound to good for our 4 cat O2 sensors exhausts combinations.
Then back to Google and found this sensible comment from 2009 giving the best advice "Howdy! IF your oil gets really nasty within a couple hundred miles, then you might need to flush it. Tranny fluid is an old Shade Tree Mechanic method, I would stay away from that, and over the counter products also. I FLUSHED and engine once, and it started leaking like a sieve. Never again for me. If I pickup a rig with a really dirty engine, I just do oil changes every 1000 till it starts looking normal. John" https://forum.ih8mud.com/threads/eng...vs-bad.269724/
Also confirms you advice Paul and what I felt myself is the less risky option. Replacing oil and filter every 1000 km from now on until the internals start looking clean again.
10-16-2018, 05:33 AM
2007 S8 V10 Oil filter horror & blocked oil pick up screen @ 85000 km
