I have an 2000 A6, 2.7 Biturbo. Interesting thing happened today.
It was parked outside, about -9C and I started it up. It started well, seemed like there might have been an excessive amount of white exhaust color, but nothing too bad. I let it warm up for 5-10 minutes before I drove away. Then in the review mirror I noticed that the excessive exhaust was still there, and it was tinged with blue. I have had a blown turbo before, years ago on an Audi 5000, so this looked like classic blown turbo. Almost no smoke until you let off the gas and then there is a massive amount of blue smoke. By the look of the smoke and quantity of it, I thought, "Ok, one or both turbos are shot."
I went to a garage/performance shop and told them I need a quote to replace the turbos. (Car has 210 000 km, so the turbos are getting older.) They told me they will get back to me next week as they were just closing. I continue to my next errand and the car started to reach normal operating temps. When that happened, all traces of smoke and excessive exhaust disappeared, and its normal again.
I have never heard of a turbo doing this. I guess its possible the turbos aren't the issue, and that it might have been caused by oil in the exhaust. Not sure how oil would get in the exhaust, and the amount of blue would seem to indicate that it was more than valve seals. The cars performance seems normal.
Any thoughts?
As well, if I need to replace the turbos, what do you recommend? Rebuild both? replace them with something of more performance? Its a 7 year old car, I like it, but its unlikely I willl keep it more than another 2-3 years so I don't want to spend a tonne of cash on aftermarket turbos.
I have never noticed this before when its been -20C and I have started it up. Its not 'supposed' to do that obviously, -9C is well within normal operating parameters for this car.
I still need to check the oil, its possible it could be slightly overfull and that the low temperature caused some strange issue with excessive oil. I honestly don't think its overfull, but I still need to verify it. Even still, I don't see how overfull oil would cause this issue and get into the intake/turbos/exhaust.
the temps are low enough to see smoke at -9C but would dissipate when the engine was warmed up, as for oil in the system it could be a bad PCV and small amounts of oil could have got past it into the breather pipe and that's not uncommon
At this point, I am just going to monitor it, if it gets worse, or repeats, then I will replace them. I am also going to do some aftermarket turbo research and see what my options are.
Freaky coincidence, but mine did nearly the same thing yesterday. No joke. Daytime temp was around 20F. I drove about 3/4 mile to post office, turned it off for about 10 mins to get mail. Started driving again, and as I got into the throttle to avoid being overtaken by some young punk in a pickup, I noticed things looked hazy behind. By the time I drove the three miles home, an embarising amount of white smoke was pluming behind me. Definitely worse whenever I used the throttle. Performance seemed alright. When I parked in my garage, I notice smoke appeared to be coming out of both pipes. It smelled pretty bad, and I though it was familiar of antifreeze and oil smoke combined. I first suspected bad fuel, but it has been more than 30 miles since my last fill-up, and I haven't noticed any trouble till now. Head gasket would likely lead to smoke from one side of the exhaust, not both. After looking in my repair manual, I am suspicious of a turbo gone bad as they are supplied by both oil and coolant, and if things went awry, this could lead to leaks into both intake and exhaust. I've only owned the car about 6 months. Had 62k mi when I bought it, and now has around 68k mi. Has alway worked great up till now.
Let me know if you discover the source of your trouble, as mine may be the same. Nearest dealer is 100 mi away, and I'm nervous to drive more than a few miles at this point.
Have done some more research on this issue, there is some posting on Audi-World that talk about a blocked breather line causing this. Could be excess pressure in the crank case. I think what they are referring to is PCV valve related. It's likely that the colder temperatures cause either a component to fail, or there is moisture in the system that causes a block that melts out or causes a valve to not open properly. I will continue to explore. If anyone else has knowledge in this issue and can add anything, please do. It was -9 today and it was fine.
Well, they are pretty much always called a PCV valve, but alot of people are referring to it as a Breather Line, or the PCV value is connected to the Breather line. A quick hunt on Drive line yielded a part. #... Not sure if this is what they are referring to. At this point its not done it again so I have not investigated it further. The temperature has not been as cold etiher for the last 1-2 days. If you look on Audi World, you can likely find a reference if you search for 'Breather line".
Posts: 5085
Joined: 2/24/2007 From: Sacramento, CA Status: online
If you wanna know where it is, look at the silver Y turbo pipe, on the back on the driver's side you will see a black "hockey puck" looking valve there, thats the A.K.A PCV valve.
Checked the AudiWorld forums. Hard to get promptly meaningful info. Every time having difficulties to get a useful info; the format of the posts is kind of old fashioned and cumbersome.
The full sized photos of shiny cars is not what the forum is for. Show some discretion… Many of us are using the forum during business hours a having cars and girls on the screen is not the most attractive event..
Please…
< Message edited by nemohm -- 12/18/2007 10:14:11 AM >
Posts: 5085
Joined: 2/24/2007 From: Sacramento, CA Status: online
I guess it could be called the breather pump valve, if it looks like that hockey puck thing i described then thats the correct part. Can you see it on your engine?
I spoke to the parts department at my (only) dealership in town. The partsperson has no idea what pcv or breather valve is. He faxed me an Etka schematic where I have not yet identified a component that resembles the valve from the photo (AudiWorld).
Is it possible the BEL engines not to have that infamous valve?
< Message edited by nemohm -- 12/19/2007 8:03:38 AM >
nemohm: if you are using firefox, use adblock plugin (i believe) and it will block all signature pictures and adds. You have to manually tell it which pics to block, but once all set up, you only see posts, no annoying pics of half naked girls sprawled over a car at work/anywhere. My belief is we all own A6's, why do I want to see what your A6 looks like, I know what an A6 looks like.
Breather pump valve (as on the photo on AudiWorld) is called suction pump, feature om 1.8T engines only. There is no pcv or other ventilation valves on 2.7T (as there is no documentation - even dealers said "no"). If somebody has proof of existance, please provide photos.
Posts: 5085
Joined: 2/24/2007 From: Sacramento, CA Status: online
A suction jet pump on a 1.8T is not even close to a PCV valve. This is the PCV vlave on my S4 2.7T, if you don't have this then you don't have a PCV valve. "puck valve"
Posts: 5085
Joined: 2/24/2007 From: Sacramento, CA Status: online
Man i don't know, ELSA Web (what techs have) doesn't even say anything about a PCV valve, but i do know for a fact thats what the valve is, and the dealer can identify it on ETKA if you point it out on the picture to them.
Its called a pressure regulating valve in the Bentley manual...go to Repair Manuals then to Fuel Injection & Ignition, then 2.7 engine codes, then Multi Port Fuel Injection, then Vacuum Sys. Layout, then to Crankcase Ventilation.
I am going to talk to the dealer tonight and find out what its named and buy it. My car did the smoking thing again, so I pulled the dip stick to confirm. Wow, thats alot od pressure that builds up, I can definately see how that could blow the seals if you left it that way, I`d say there had to be 10-20 lbs pressure, hard to say really, but it did cause a good hiss of air and `splurt`of oil. Had to drive the car, so I left the dipstick slightly out, hoping the part with thaw out for the drive home. Either way, I shall get the name of the part from Audi tonight.
Indeed, Bentley (ElsaWin) refers to the unit as “pressure regulating valve” - drawing A24-0174 (correctly stated by AdLucem). For my surprise there is a drawing A24-0175- Suction jet pump (automatic transmission). The 3-way pump is the one from the AudiWorld article. (My dealer suggested there is no Suction jet pump on 2.7 engines, but only on 1.8).
Etka has a drawing and part # for the suction pump (listed for manual transmission); the pressure regulating valve is shown on the global vacuum diagram, but w/o part#. (Part# only for the breather hose connected to the valve),.
Any way for troubleshooting the Crankcase ventilation system, and specifically the pressure valve and suction pump? Any practical experience around the vacuum system and related components?
( There are indications for vacuum system applications used in normal and for cold climate. (It seems to me moving cars among climate zones could be a tricky thing to do).
< Message edited by nemohm -- 1/2/2008 12:27:28 PM >
Had same problem yesterday on my '01 A6-2.7t Automatic. 7 degrees F when started car in the morning. Lots of smoke until shut car down for around 5 minutes and then no smoke afterwards. Oil dripping from tailpipes, but no more smoke. Sounds like similar problem as one posted on AudiWorld that described a blocked or frozen breather hose. Appears to be a common problem in cold weather. The part that I think I need is 078 103 235 G.
Printable Version
Strange Turbo Issue - 
RE: Strange Turbo Issue - 
