Few small problems with my 07 A8 with 13k miles....pls help
#51
AudiWorld Super User
Agreed, but it turns pretty brown just w/ use
Mine looks green when it goes in, but ends up used oil brown over a couple of years.
I haven't figured out a good place to open the W12 system, but I used to flush the C5 4.2 just by opening it at the cooler tube clamps while sucking fresh fluid from a can. Even w/ that is was closer to brown than green after a few more years.
The accumulators went out with the C3 (5000) we both shared. By the C4 it was back to conventional vacuum driven power brakes, and that accumulator was in there to hold pressure to make the brakes somewhat usable if engine cut and at low engine RPMs if pressure was low. They dialed the normal operating pressure way back after the C3 too; perhaps like me you had an exploding high pressure hose..or two..at the fittings before they got the system ready for prime time in later generations.
I haven't figured out a good place to open the W12 system, but I used to flush the C5 4.2 just by opening it at the cooler tube clamps while sucking fresh fluid from a can. Even w/ that is was closer to brown than green after a few more years.
The accumulators went out with the C3 (5000) we both shared. By the C4 it was back to conventional vacuum driven power brakes, and that accumulator was in there to hold pressure to make the brakes somewhat usable if engine cut and at low engine RPMs if pressure was low. They dialed the normal operating pressure way back after the C3 too; perhaps like me you had an exploding high pressure hose..or two..at the fittings before they got the system ready for prime time in later generations.
Last edited by MP4.2+6.0; 02-14-2014 at 08:11 PM.
#53
AudiWorld Member
IF this turns out to be a Power Steering leak, and your fluid is brown or black, it DOES need replacing (well, if it's that color, whether you have a leak or not, it needs replacing!).
I assume this is the same fluid Mercedes uses in their PS and ABC hydraulic suspension systems - green when new and becomes dark brown/black over time. When it is dark tan it is time to replace, and black is past time to replace (but, servicing is not noted in owners manuals, a so called 'lifetime' fluid - HA - just means the life of the component is shortened, in my opinion).
You can buy replacement fluid at the dealer (Audi or MB), OR you can buy a liter or two of Pentosin CHF 11S. This is the producer of the fluid, and it is about half the price of Audi/MB. It's available at several internet outlets, or at NAPA (may not be in stock). I bought a dozen liters at NAPA for less than $20 per liter, and Amazon has a 20 liter jug for ~$215.
Gary--
I assume this is the same fluid Mercedes uses in their PS and ABC hydraulic suspension systems - green when new and becomes dark brown/black over time. When it is dark tan it is time to replace, and black is past time to replace (but, servicing is not noted in owners manuals, a so called 'lifetime' fluid - HA - just means the life of the component is shortened, in my opinion).
You can buy replacement fluid at the dealer (Audi or MB), OR you can buy a liter or two of Pentosin CHF 11S. This is the producer of the fluid, and it is about half the price of Audi/MB. It's available at several internet outlets, or at NAPA (may not be in stock). I bought a dozen liters at NAPA for less than $20 per liter, and Amazon has a 20 liter jug for ~$215.
Gary--
Last edited by Gary Knox; 02-15-2014 at 05:10 AM.
#54
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So, do you all think the leak just magically disappeared? I cleaned the entire area with brake fluid this morning. I have drove over 100 miles today...and every time I stopped, I pulled the fog light bezel and it is as clean as brand new...zero signs of a leak.
Could the very cold weather caused some sort of a temporary leak?
Could the very cold weather caused some sort of a temporary leak?
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#57
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Again, you really don't have enough info here...
I'm a bit of a broken record here, but not enough info. w/ the ownership transition. If the power steering reservoir was overfilled (up to near the very top) when car was cold, it can expand and overflow. That can happen the next time car gets really hot, which could be rarely in winter--a warmer day, lots of stop and go, etc. If it was run almost empty and then filled, it can foam as the pump re-primes and can then overflow if not filled gradually and watched carefully. If parked ultimately on a greater slope than normal, can run out from the belly pan at that point. None of these scenarios is covered in the background info. that I saw, thus I can't do more than speculate.
Going forward, check it cold and get it to the lower/min. mark or a bit more. Then check it periodically to make sure it holds. It doesn't magically disappear or evaporate, so if it holds it was one of the kinds of scenarios I mentioned. If it drops against a known prior measurement (cold to cold), then of course there is a leak hiding somewhere.
Going forward, check it cold and get it to the lower/min. mark or a bit more. Then check it periodically to make sure it holds. It doesn't magically disappear or evaporate, so if it holds it was one of the kinds of scenarios I mentioned. If it drops against a known prior measurement (cold to cold), then of course there is a leak hiding somewhere.
Last edited by MP4.2+6.0; 02-15-2014 at 08:46 PM.
#58
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well, the TPMS was fixed..just bought 5X new sensors as recommended by mishar. Still have the ventilated seat problem.
Still dunno what happened with the power steering issue, it hasn't leaked in months. I can only think it had to be the cold weather.
Still dunno what happened with the power steering issue, it hasn't leaked in months. I can only think it had to be the cold weather.
#59
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Vented seat - It does look like the temperature sensor or the fan on the passenger side is loose or unplugged. Check the heated seat to see if it works, if it does, then the fan has no load.
Cheers,
Louis
Cheers,
Louis
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