my own 2.7T odd sound at startup
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Elder Member
Joined: Mar 2000
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my own 2.7T odd sound at startup
Right at startup, under any kind of pedal pressure, my car makes a tapping sound like valve tapping or spark knock. This stops after 30 seconds or so.
It has done this on several tanks of gas from different vendors (all 92 octane).
I'm slightly concerned, for a while I thought it was just Audi purposely knocking the engine a little at startup to heat up the cylinders faster. I read somewhere that they do disable the knock sensor for a short time at startup.
Now, I'm not so sure. Anyone else have this or care?
It basically makes your engine sound like a (quiet) diesel for 15-30 seconds at startup.
It has done this on several tanks of gas from different vendors (all 92 octane).
I'm slightly concerned, for a while I thought it was just Audi purposely knocking the engine a little at startup to heat up the cylinders faster. I read somewhere that they do disable the knock sensor for a short time at startup.
Now, I'm not so sure. Anyone else have this or care?
It basically makes your engine sound like a (quiet) diesel for 15-30 seconds at startup.
Junior Member
Joined: Mar 2000
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This may be no help Steve,
other than to suggest a visit to the dealer. I have that exact symptom (which started about a month ago) in a Eagle Talon AWD turbo. Any attempt to accelerate causes that tapping sound you mention and it lasts about the same time. If I accelerate very slowly it can not be heard and everything seems normal after it stops.
My layman theory is a partial oil blockage to a valve train component (lifter/rocker) since temperature doesn't seem to be a factor with mine. I also noticed an exhaust smell that seems to stop when the tapping stops.
My 2.7 T does not do this by the way.
I sure would like to know what this is, especially in your 2.7 T and sincerly hope it is not a major or time consuming fix (if needed).
Good luck.
..../jp
My layman theory is a partial oil blockage to a valve train component (lifter/rocker) since temperature doesn't seem to be a factor with mine. I also noticed an exhaust smell that seems to stop when the tapping stops.
My 2.7 T does not do this by the way.
I sure would like to know what this is, especially in your 2.7 T and sincerly hope it is not a major or time consuming fix (if needed).
Good luck.
..../jp
New Member
Joined: Mar 2000
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Having a wonderful grasp of the obvious, ...
I say call the dealer asap. Mine does not do this, and in my layman's mind (as yours I'm sure)it does indeed sound like an oil circulation issue. Is an oil sending switch involved in actual circulation or just indication? Oil pump?Please let us know what the dlr says. Hope it's not serious.
New Member
Joined: Mar 2000
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Re: my own 2.7T odd sound at startup
This sounds like a hydralic lifter problem (or maybe not) The oil pressure from the engine pumps the hydralic lifters up. If you have very light oil this can make the valve train have a tapping sound at idle as the oil pressure is on the low side and the oil can leak of the lifter rapidly becuse it si light weight. My 90' Eagle talon always did this at idle somedays worse than others but it alwasy seemed to go away evnetually. It could also be that the oil pressue is low at idle and the oil takes a while to work its way into the lifter due to the oil being cool and all. Bottom line is if you are concernec then take it to the dealer.
-p
-p
AudiWorld Uber User
Joined: Mar 2000
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Sounds like valve lifter noise
there should be a very brief tapping/whirring sound for 3 or so seconds on start-up. These are the lifters getting oil. There should also be moan/hiss from the air injection pump for a minute or so.
See your dealer as soon as you can.
See your dealer as soon as you can.
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