Basically I've tried to install a few mods I like recently and installed the roc-euro intake 8 days ago. Everything was going good until today during the end of a longer weekend drive I heard a squealing that isn't normal. I pulled off at my normal gas station and lo and behold the intake pipe had fallen loose. No biggie, I even pushed it back in place with the vehicle running and retightened the clamp, the noise still persisted. I went ahead and drove home about 10 minutes away, took the intake completely apart, retightened the clamps, and put everything back in place. Noise is still there. Vehicle hasn't been all the way cold yet to see if it's there on cold start, oil cap is vacuumed on and still makes noise after breaking vacuum, and I can't find any air leaks but of course I'll look more when it's daylight. This noise also completely goes away around 3-3.5k rpm and above (around when you can hear the supercharger whine). I'll try to attach a 45 second video of starting the car at temp, letting it run, and shutting it off. Thanks in advance.

Edit: figured I'd put just in case car is a 2015 premium plus 3.0t tfsi with 62k miles

 

That sounds like a pulley or belt slipping to me. I always say if the car is doing something different from when it was worked, it's something you did or forgot to do. Check your work again.

 

Remember, you have TWO belt systems and belt tensioners...one for the Serpentine belt driving all the norms stuff, and one dedicated circuit/belt/system just for the supercharger, etc. The squealing noise issue may or not be related to what you did, but if you didn't touch the belts systems or break any lines/connectors, then I'm guessing it's just unlucky. That, or the car didn't like what you did to it!

Offhand, I'd say if the noise abates just from revving engine higher, then it's likely related to the belts/idlers/tensioners systems. The 'oil cap vacuumed on' is often a related symptom of a failed PCV on the 3.0T engine though, and another symptom of failed PCV is a distinct screeching sound manifesting from the air vacuum formed in crankcase sucking air through seals/o-rings...anywhere it can basically. If you can pull the dipstick or remove the oil cap and noise immediately goes away when pressure is equalized, that's likely a failed PCV, so that's an easy check to rule out drive belt(s) systems issues.

On the PCV...symptom-wise, it won't make the noise immediately at cold start as the vacuum has to build up in crankcase first, etc., and the noise gets worse over time too; it should make you very uncomfortable to hear the screech related to the PCV, whereas a belt squeal sounds somewhat different and you'll be smelling burn't /hot rubber odor from the belt slippage normally. Do the easy checks first...let it make the noise, then pull the dipstick/oil cap, etc.

Good luck! There is a TSB/recall on those PCVs also, but not sure if it covers your year model...maybe?

 

Interesting that the noise persists briefly after shutting off the engine. So, I think that points more toward a vacuum or pressure issue than a pulley, but it is certainly worth checking all suspects.

 

same, seems like he might of damaged some of the vacuum lines when messing with the install, or they got loose/damaged when the hose poped off causing some pressure issue

 

Figured I would post an update for you guys since everyone is still genuinely trying to help. I've started down the route of pcv replacement due to yesterday during further diagnostics I found the noise isn't present until engine gets all the way up to temp and noise completely goes away starting car without oil cap on. Since my warranty does not cover pcv valves and I'm not paying over $1k for repairs unless necessary I'm cracking the engine open this weekend and replacing pcv, thermostat, and check valve mod. Here's to hoping no hoses get cracked and the parts get here in time since my next opportunity for the fix won't be until 3 weeks from now lol. Man that noise is annoying

 

Thanks for the update! The PCV is a common repair on that engine, so there should be parts lists reasonably available for what is recommended to replace while in there. If you can get parts numbers for the hoses, you should go ahead and replace them. Those are among the "better safe than sorry" category for parts replacements, particularly when you have difficult to access repairs to perform and the parts themselves are relatively inexpensive!

 

Figured I would revive the thread and give an update. I did not bite off more than I can chew with the intake lol, it was indeed the pcv that had failed. Almost two weeks later (due to repairing in the driveway and continuous thunderstorms) I finally got the Q7 threw back together. Pcv replacement, thermostat upgrade, and check valve mod. Vehicle runs great after the first initial horrible start, test drove decently hard and no new leaks or check lights thank the Lord. Only downside is the battery was a little on the older side and I managed to kill it completely twice so that's next on the list. Thank you to all who helped or gave an opinion, I went into this job blind with this being my hardest diy yet so hopefully it only gets better from here 😂

 

Thank you for providing the update! It's always great to hear what/how things went down. If nothing else, just to put closure on the topic.

 

what is this "check valve mod"?