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Just curious what everyone thinks. I have listened to a couple of Itooz Youtube videos and they sound close. However it is a bit harder to hear his engine due to the mic quality, but the engine noise is audible. I am going to take it to my indy mechanic to see what he thinks. Also asked MP4 to which he said it sounds like normal valve train noises. I just think it is me worrying about something that is fine, which I do a lot with my cars.
... Also asked MP4 to which he said it sounds like normal valve train noises....
To be clear, arguably in the range of normal for a higher mileage one if not showing any other obvious symptoms. Somewhat louder than I would expect though for one with no issues and/or younger, and there is some apparent slight valve ticking as you move around the motor. Thus, your concern is not misplaced.
It may be you had a very sensitive mic or something. When I was in front of my C5 4.2, often the loudest thing I heard was stuff in the serp belt drive--P/S, A/C, slight belt running noises, etc. The C5 had more trim cover stuff though than the D3 4.2's do, and that may have softened the sounds a bit.
To be clear, arguably in the range of normal for a higher mileage one if not showing any other obvious symptoms. Somewhat louder than I would expect though for one with no issues and/or younger, and there is some apparent slight valve ticking as you move around the motor. Thus, your concern is not misplaced.
It may be you had a very sensitive mic or something. When I was in front of my C5 4.2, often the loudest thing I heard was stuff in the serp belt drive--P/S, A/C, slight belt running noises, etc. The C5 had more trim cover stuff though than the D3 4.2's do, and that may have softened the sounds a bit.
I thought the valve ticking is just the fact of having hydraulic valve lifters? And to be honest I think it is the mic as well, because I could not hear almost any of the noise when standing over the engine. Also the engine is crazy quite compared to my previous 2001 740iL. Which also with age and mileage has lifter tick. And on the topic of issues there isn't any other apparent issues other than the oil retention valves I am going to be changing very soon. Which are also referred to as check valves, so that may have to do with the slightly louder engine noise. Finally whenever the car was service twice by Audi, once before I purchased the car and right after, it had two full inspections. Wouldn't Audi have caught it either time if the idle noise was not right?
I thought the valve ticking is just the fact of having hydraulic valve lifters? And to be honest I think it is the mic as well, because I could not hear almost any of the noise when standing over the engine. Also the engine is crazy quite compared to my previous 2001 740iL. Which also with age and mileage has lifter tick. And on the topic of issues there isn't any other apparent issues other than the oil retention valves I am going to be changing very soon. Which are also referred to as check valves, so that may have to do with the slightly louder engine noise. Finally whenever the car was service twice by Audi, once before I purchased the car and right after, it had two full inspections. Wouldn't Audi have caught it either time if the idle noise was not right?
There are quieter lifters and less quiet ones. Newer are usually quieter than older. There are also bigger and smaller sized lifters BTW, and the Audi 4.2 ones are really tiny compared to older designs I got into; I would expect less noise as they get small, plus with 40V they should blend in more with less individual ticking than something like my first lifter Audi, a 10V 1985 Audi 5000. On my 114K miles W12, everything is fine sewing machine (48V) and soft so not noise I expect there.
I would have to hear in person to sort out recording related differences; could be as you say that in person mechanics think all is normal. If it seems somewhat loud, as before I would Risoline treat it, and would do that before the drawback/check valves since its easy and pretty cheap--mostly the cost of an oil change. You could also go to a 5W-50 type oil. As a CA car, no big deal to go heavier if any reason to (sound, burning, whatever). Standard Audi CA fill at the dealers pre-Audi standards in the mid 80's was old classic Castrol 20W-50.
Did a little searching with an automotive stethoscope and found the engine and valves to be quite very quite. The loud bit in my video as found by the stethoscope was the injectors and regulator. They are beastly loud. MP4 the reason you probably don't hear yours is the direct injection and also the massive sound cover they put over your engine. Here is the stethoscope I used:
It is only a few dollars from an auto store but priceless when finding noises.
Did a little searching with an automotive stethoscope and found the engine and valves to be quite very quite. The loud bit in my video as found by the stethoscope was the injectors and regulator. They are beastly loud. MP4 the reason you probably don't hear yours is the direct injection and also the massive sound cover they put over your engine. Here is the stethoscope I used:
It is only a few dollars from an auto store but priceless when finding noises.
Good job with the stethoscope. Cheap, low-tech, and highly dependable. Any diagnostic technician should have one in the toolbox.
MP4's D3 is not direct-injected, but rather MPFI. It's actually common for direct-injection motors to exhibit louder ticking noises due to the high pressure pump and injectors.
Good job with the stethoscope. Cheap, low-tech, and highly dependable. Any diagnostic technician should have one in the toolbox.
MP4's D3 is not direct-injected, but rather MPFI. It's actually common for direct-injection motors to exhibit louder ticking noises due to the high pressure pump and injectors.
So is MPFI still injectors? I guess the sound shield and cover just masks the noise of them on the W12.
All sounds pretty normal and just like mine which is an 04.
The W12 and early V8 are port injection rather than direct injection. The V10 and '07 on FSI V8 are direct injection though. DI systems are generally noisier because of the very high pressures involved. However standard injectors still make audible ticking noises.
Yes, D3 W12 is port injection, 4V. It is quieter, though perhaps in part because it has the chain drive in back with internal covers, and also because the intake manifold covers virtually the whole top of motor. OP may have been referring to my 2000 A6 4.2, which is similar to the D3 pre FSI 4.2, except it has a lot of trim covers that conceal both a lot of the the intake area like the D3 4.2, but also over most of the valve covers.
For OP, one suggestion, since you have found the apparent louder noise to be in large measure with the injectors, run Techron through it for a few cycles and see if it does any good. As far as the regulator, no experience with issues on my various Audi's. Probably won't do anything, but consider a fuel filter change as just good general maintenance
07-21-2015, 10:31 PM
Normal Engine Noise?
