Here is an unusual one. Some sort of intermittent clicking noise that appears at random intervals. Sounds metallic and is on the belt side of engine by alternator. The noise comes and goes. I have not checked the tensioners and pulleys. Here is what I know now. Tensioner is not flopping around and belt runs smoothly. Water pump is not leaking. AC works fine. Charge rate is 14.3 or so. I can get on a lift and start digging later this week. Sometimes the noise sounds like it's between the alternator and the cylinder head. It does not sound like a typical rotating part noise.
2012 2.5 five cylinder Sportwagen noise by belt side of engine
- Thread starter RabbitGTI
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Beat tool i have for diagnosing strange noises like the one you describe is a mechanic's stethoscope.
They're available at harbor freight and most auto supply places for relatively cheap. You can use it to isolate where the noise is coming from.
They're available at harbor freight and most auto supply places for relatively cheap. You can use it to isolate where the noise is coming from.
Mozambiquer
Vendor , w/Business number
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Check the alternator clutch pulley, that's a very common cause of that kind of noises.
1854sailor
Resident Curmudgeon
It's not a diesel, so does it even have a clutched alternator pulley?
Mozambiquer
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- 2004 VW Touareg V10 TDI, 2012 Audi Q7 V6 TDI, 1998 VW Jetta TDI. 1982 VW Rabbit pickup, 2001 VW Jetta TDI, 2005 VW Passat wagon TDI X3, 2001 VW golf TDI, 1980 VW rabbit pickup,
Yes, they do have a clutch pulley. The one they use is this one: INA clutch pulley
oilhammer
Certified Volkswagen Nut & Vendor
I vote for alternator pulley, too.
Take the lower belt off (this drives the A/C compressor, which has a secondary belt that runs everything else). Then start the engine and see if the noise goes away. That will at least verify it is something in the accessory drive. There really isn't anything else up there to make any noise, though.
I find a lot of the 2.5L engines start to have sticky secondary belt tensioner springs, too.
Take the lower belt off (this drives the A/C compressor, which has a secondary belt that runs everything else). Then start the engine and see if the noise goes away. That will at least verify it is something in the accessory drive. There really isn't anything else up there to make any noise, though.
I find a lot of the 2.5L engines start to have sticky secondary belt tensioner springs, too.
1854sailor
Resident Curmudgeon
Thanks for splainin'...
The noise went away the day after I posted. Only a very occasional faint sound since then. I released the tension on the belts and the tensioners, pulleys and water pump seem fine. The pully on the alternator spins both ways and seems smooth. It does make a whining noise when turned counterclockwise, what is that? I did not lock the alternator shaft to test if the pully locks in only the clockwise position. Not sure of the safe way to lock the shaft. How do you do that? I also put the stethoscope on various things and heard a noise similar to what I heard coming from the alternator body. Maybe it's something in the alternator making the noise (bearing?). Will check if the alternator pully locks clockwise tomorrow.
Mozambiquer
Vendor , w/Business number
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- TDI
- 2004 VW Touareg V10 TDI, 2012 Audi Q7 V6 TDI, 1998 VW Jetta TDI. 1982 VW Rabbit pickup, 2001 VW Jetta TDI, 2005 VW Passat wagon TDI X3, 2001 VW golf TDI, 1980 VW rabbit pickup,
That whining sound going counter clockwise would be the brushes chattering a bit as you turn it. That's normal.
I use a screw driver to stick into the front of the alternator, being careful not to damage the stator wires. I actually normally do a twisting twitch motion where I spin the alternator and then rapidly twist the pulley backwards with my hand. I've done it so many times, I can feel whether it's good or not, simply by doing that.
The screwdriver in the rotor is the more failsafe way if you haven't done it so much.
oilhammer
Certified Volkswagen Nut & Vendor
Yep, what he said. That is exactly how I check them too.
1854sailor
Resident Curmudgeon
I have a wooden chopstick in my toolbox, which I use for that...
oilhammer
Certified Volkswagen Nut & Vendor
That was Mozam said. And that's what I do, too. Only works if the belt is off, though.
DivineChaos
Top Post Dawg
My alt clutch pully randomly makes noise. If I put my hand on the alt it gets quieter. Alternatively it could be a failing serp tensioner.