Audi S4 with oil issue - help much appreciated

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This is my first post here, so just a little background on the car in question... It's a 2000 Audi S4, with factory upgraded european RS4 turbos, this that and the other thing. I have 106K on the stock motor and have been running OW-30 German Castrol for the past 30K or so since I bought the car, with a few changes of TOTAL/ELF 5-40... My issue is this. When I start my car in the morning or anytime for that matter, I don't get any smoking from the exhaust, just loud! (I run straight pipes - all cats removed until my True-dual exhaust system).. When driving on constant throttle I get no smoke at all.. However, once the car is warm and I hit traffic and I engage in first or second from a roll or standstill, I will puff out a white/blueish tint of exhaust smoke and it smells very similar to the exhaust of a two stroke motor. My question is this.. I've been told to stop using OW-30 oil in my car since it's too thin for my application. I just bought some TOTAL/ELF 5W-40 once again because I had good luck with that oil last time. People are saying maybe your valve guides or rings are going bad, but I have Blackstone lab reports saying wear metals very very low for 106K etc etc. I just replaced the PCV line in my car, and I'm going to add a AMW Catchcan to help. Do you think running the thicker oil as well as a catchcan may help my issue? Thanks for the help, sorry for long post! -To add, people say when you have those valve guide issues or ring issues you have other associated problems with the car. I have no problems, and the motor makes around 500HP/520TQ @ crank.
 
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running the thicker oil will help a little. but yes, you likely have some wear in the rings or valve guides; possibly valve stem seals. as you back off the throttle it changes the pressure in the cylinders and sucks the oil in. I am not familiar with the specifics of the audi/vw motors, but in my car the most common reason for this problem is valve stem seals, which is relatively easy to fix. perhaps camp out on the vwvortex website and see what they know.
 
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Just some general thoughts. I'd run a compression check on the cylinders. That'll help identify if you have some possible ring or valve seal issues if a cylinder or 2 look low. Also since you said you're using turbos from an RS4, I'm assuming they are used? Is it possible the seals on the turbo shafts are starting to fail? I'd also run a thicker oil in that application. The turbos are definitely going to heat up and thin out that oil. I'm curious as to what viscosity Audi recommends for the S4/RS4 engines. Ed B.
 

JAG

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Maybe the flow to the turbos is too high so a restrictor I the line(a) is needed? I think valve guides/seals issue usually shows itself by smoke happening during start up which you do not experience. Worn rings seems unlikely given the engines relatively young age. I would get compression and leakdown tests first. If good, then the turbo issue I mentioned is what I'd look into. I agree that GC could be too thin for your application. A lot of euro 40 weight oils will shear down near the viscosity of GC so I'd use something that will remain solidly in the 40 weight or even be on the low end of 50 weight. Spiking 40 weight oils with Mobil 1 15W-50 is one way to do that.
 

AudiSport

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To answer some questions... When I say the turbos are from an RS4, they are OEM for the RS4. I bought them brand new, they are BorgWarner K04-025 and 026 turbos. I'm hoping the oil will show some improvement, and I will get a compression test done @ the time I install the Oil catch can.. People on the audi forums are thinking it could be as simple as PCV. The stock PCV system is really a joke especially when the car is running twice the factory HP. Thanks for the replies though, I've had a compression test done before maybe 10K ago and everything was OK, so I'll see how it looks this time around. I also want to say, if I just let off throttle I don't see this smoke, it's strictly when engaging in gear from a slow roll... That's why people are saying possibly PCV.
 
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This is quite common on highly tuned turbo engines, usually it is the rear seal in the turbo that seeps oil under vacuum/idle conditions. If this is where the oil is coming from it is quite common and not really a big issue.
 
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Disconnect the pcv line and run it to a temporary catch can to see, but I really doubt that is the problem. Full throttle at low RPM is the lowest intake vacuum condition, I doubt it would pull oil through there. No smoke on startup? That makes me think the valve guides are fine and perhaps a Fredric has a good idea, I'm not knowlegeable on turbos.
 

AudiSport

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Oh okay. I just wish I could pinpoint it... If it adds to anything, I don't lose any oil on my dipstick when reguarlay checked.
 

AudiSport

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I also want to add this, sorry I keep adding little things just pop into my head at random times that I forgot to mention.. At the end of my exhaust tips, the left pipe (true dual) has condensation where as the other one doesn't.. Just hazy inside as normal. When I'm on a drive and this is happening there is a little pool-up of a liquid at the end of the pipe. Now, my mechanic has told me if that is oil, it would be smoking like a S-O-B... He said it's probably just exhaust soot and water. How can I tell if that is water or not? Smelling it doesn't do anything for me, it smells like nothing. I would feel like a scientist if I had to get down with a little dropper thing and see if it mixes or not with water... haha If it is indeed water, maybe I'm just running rich. I have all these modifications done, but no Wideband O2 sensor. I go by the stock narrowband which I know is not an accurate measure of AFR.
 
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 Originally Posted By: AudiSport
It's a 2000 Audi S4, with factory upgraded european RS4 turbos, this that and the other thing.
modified engine
 Quote:
My issue is this. When I start my car in the morning or anytime for that matter, I don't get any smoking from the exhaust, just loud! (I run straight pipes - all cats removed until my True-dual exhaust system).. When driving on constant throttle I get no smoke at all..
modified exhaust
 Quote:
once the car is warm and I hit traffic and I engage in first or second from a roll or standstill, I will puff out a white/blueish tint of exhaust smoke and it smells very similar to the exhaust of a two stroke motor.
Sounds like valve stem seals are not sealing properly. The seals are made from Viton, so that will not show in a UOA. Given the increased power output, this does not surprise me, especially because it seems to me that valve stem seal issues are common with VW and Audi engines (Based on my experience with two VW and one Audi).
 Quote:
I just replaced the PCV line in my car, and I'm going to add a AMW Catchcan to help.
modified PCV system
 Quote:
To add, people say when you have those valve guide issues or ring issues you have other associated problems with the car. I have no problems, and the motor makes around 500HP/520TQ @ crank.
Your car's engine was not designed to put out 500 hp (factory hp is what, around 260 hp?). You can reasonably expect that such an increase in power comes at a cost. The 2.8 V6 Audi engine that is in my car is often being modified to put out more power. Even a 30% increase in output comes usually at a cost. If the only issue you have is a puff of blue smoke here and there, you are lucky.
 

AudiSport

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Haha thanks.. Sometimes just get a little neuoritic with little things that come up, other than that it's real healthy... Thanks though I appreciate the help. Glad I joined this forum, I used to just read it, but getting feedback on my own questions are great.
 
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You may want to also ask around on S4 forums, for example the ones on Audiworld and Quattroworld. They also have performance and tuning forums.
 
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May also be oil getting past the turbo bearings with the change in vacume. Id suggest (after the tests already suggested) M1 HM 10w40. I think its a really good option for your app, maybe 5w40 TDT in winter, maybe not.
 

AudiSport

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 Originally Posted By: moribundman
You may want to also ask around on S4 forums, for example the ones on Audiworld and Quattroworld. They also have performance and tuning forums.
Yeah, I'm on all those forums.. Mostly Audizine, but on QW a lot too... Audiworld has turned into the new NOOB fest You'll get responses like, turbos are blown! haha.
 
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Hi there, got the same car but I am still running k03s modded to stg 2+ I have been running GC without any problems, even when I track the car. factory fill is 0w-30 and manual also approves 5w-40 A3 rated oil. GC should be fine for street use in your case. my understanding is that you are getting smoke puffs only between shifts(n to 1st and 1st to 2nd?) and off throttle? if valve guides are bad you would have start up smoke in the morning. I doubt that the pcv system is to blame since you are not boosting when you get the smoke. could be that your turbo seals have small leak on the exhaust side...check the lower intercooler hoses for any oil also if you have VAG-COM check block 32 for your long term fuel trim..maybe you are running pig rich and since you don't have cats it could show as smoke...
 
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