# 2012 Passat 2.5 rattle



## nicko (Jul 29, 2000)

Have anyone experience a rattle at low speed from the engine on a 2.5 inline 2012 Passat Auto. It kinda sound like the shifter rod rattle that I had in my GTI. I can't seem to reproduce it at will but it is annoying.


----------



## brsexton (Mar 30, 2012)

Not sure if it's the same, but my 2012 Passat 2.5 has a rattle as well that only happens once or twice a month. So this is how it goes. I start the car first thing in the morning to head to work. Everything is fine when started and I back out of the driveway. As soon as I take off, I hear a rattle noise only after the car starts to change gears. So... no rattle, then it hits 2nd gear, rattle, then as the RPM's increase, rattle goes away, then rattle back when it his 3rd, etc. This happens less than a minute and then I don't ever hear it again until next time. It seems it corresponds with the engine heating up. If I let my car idle in the driveway for 30-45 seconds before taking off, I don't ever hear it. I will say that it has done this since new, but since it is so difficult to duplicate, I never mentioned it to the dealer.


----------



## karlsvw (Oct 25, 2014)

With a heat cycle involved, it makes me wonder if it's an exhaust issue? Can you isolate the noise? Under the hood? Under the floorboards? In the rear? I have not heard of this in the 2.5 but you also could be hearing piston slap. When cold, the piston tolerances could be a bit on the loose side. This is not a good thing and should be investigated further.


----------



## brsexton (Mar 30, 2012)

karlsvw said:


> With a heat cycle involved, it makes me wonder if it's an exhaust issue? Can you isolate the noise? Under the hood? Under the floorboards? In the rear? I have not heard of this in the 2.5 but you also could be hearing piston slap. When cold, the piston tolerances could be a bit on the loose side. This is not a good thing and should be investigated further.


I was thinking it may be exhaust related as well, however it does sound like it is coming from under the hood. It does not sound like piston slap or rod knock that I've ever heard before. The noise is so brief that it is really hard to pinpoint the exact location. I haven't heard it for weeks now which is pretty typical. Having owned this car for almost 4 years, I've just chalked it off as a quirk because the odds are I'll never figure out what it is.


----------



## karlsvw (Oct 25, 2014)

Hmmm. Is this an automatic? With a manual, you might suspect the throw out bearing. With an automatic, all sorts of things go on in there. (LOL) But since its happening when it shifts, I would say it's transmission related. But, hard to say. I would have to hear it.


----------



## brsexton (Mar 30, 2012)

karlsvw said:


> Hmmm. Is this an automatic? With a manual, you might suspect the throw out bearing. With an automatic, all sorts of things go on in there. (LOL) But since its happening when it shifts, I would say it's transmission related. But, hard to say. I would have to hear it.



The car is an auto. I feel like the only reason I hear it when it shifts is because the engine is at lower RPM's until it is ready to change gears again. It happens most at that low RPM range right after the car has up shifted. I am still thinking a loose heat shield or something of the sort. Whatever it is heats up very quickly and the noise is gone. I feel like if it were something more, it would have failed by now. I am getting ready to hit 40k miles. If whatever it is decides to fail later, at least I have an extended warranty.


----------



## karlsvw (Oct 25, 2014)

Well, since it has done this sense new, I wouldn't worry too much about it. But still annoying. Maybe crawl all over it when it's cold and just grab and shake things with your hands to see if something squeaks or rattles.


----------



## Ronny Bensys (Apr 17, 2014)

I am living with this rattle more than a year. Have been searching in Russian forums for a solution. Only found reasonable explanation for that being brake disc shields or covers vibrating at low speeds and sometimes making rattling noise when shifting at low speeds. People tell that their screws loosen over time.

Recently, while doing regular servicing, I took a moment and shook the shields with hands but found nothing strange. They were standing a bit loose but not free enough to generate a loud noise one can hear inside cabin.

It will be great if anybody with good recorder share video/sound.


----------



## Ronny Bensys (Apr 17, 2014)

Any updates on the subject issue? I'm trying to izolate similar rattle.


----------



## karlsvw (Oct 25, 2014)

Funny this would come up again. I noticed something similar on mine about a month ago. Has 113,000 miles now. But, I have located it to a cooling fan. Shut the car off and you here in spin down to a stop. It has been intermittent. Happening only three times in the last month. I will look at it this week and update.


----------



## Ronny Bensys (Apr 17, 2014)

I have been waiting for somebody to chime in since 2015. Glad to see you in this thread. 

Looking forward for soonest replies from others too.


----------



## karlsvw (Oct 25, 2014)

Ronny Bensys said:


> I have been waiting for somebody to chime in since 2015. Glad to see you in this thread.
> 
> Looking forward for soonest replies from others too.


No problem! I will look at the end of this week and post my findings. My first guess is that the fan is warping when hot. Then hitting something. I'll let you know.


----------

