View Full Version : A7 3.0T Startup Rattle Longer than 3 Seconds
AtmosphereA7
02-15-2021, 12:43 PM
I am aware of the timing chain tensioner issues with this engine.
I have been led to think that a mere 1-3 second rattle on the first cold-start was covered in the TSB and a non-issue. However, this is a new development I would like to ask if anyone can lend some insight.
Recently, I get startup rattle whenever the car sits for more than 10 minutes, and about 35% of the time, I get the same-old rattle; followed by milder rattle for up to 10 seconds. In addition, each time I shut the car off, I now hear several "clicks" from the tensioner as the engine shuts down.
Valpo A7
02-15-2021, 01:37 PM
If you are still under warranty then take it in for repairs. If not under warranty then get ready for a $5,000 to $7,000 repair bill. Less than $2,000 in parts if you can do it yourself.
Timing chains are on the backside of the engine which means it’s an engine out repair
5000S
02-15-2021, 03:12 PM
How many miles on the car ? That noise is disturbing, to say the least.
430hps4
02-15-2021, 04:02 PM
If not under warranty then get ready for a $5,000 to $7,000 repair bill.
Don't be afraid to reach out to a reputable local shop. My quote was under $4k for a full timing replacement set. I figured at least now I know MY number. Mine is annoying at startup, but settles down after that magical 3 seconds. If it progresses, then I'll toss $4k at it to make it go away and have peace of mind.
Valpo A7
02-15-2021, 04:23 PM
I had an Indy shop quote me $5,000 for it. Mine had progressed to getting the P0016 and P0018 engine codes that kept me from passing emissions. $4k is a much better price but still a hard pill to swallow.
5000S
02-15-2021, 07:25 PM
Don't be afraid to reach out to a reputable local shop. My quote was under $4k for a full timing replacement set. I figured at least now I know MY number. Mine is annoying at startup, but settles down after that magical 3 seconds. If it progresses, then I'll toss $4k at it to make it go away and have peace of mind.
How many miles on yours, don't be shy, it helps explain the issue.?
Valpo, same thing with you, how many miles before things went noisy ?
bahula03
02-15-2021, 07:39 PM
While the noise may very well have to do with the timing chains/tensioners (impossible to tell without hearing it), that sounds waaaaay beyond the relatively benign issue underlying the usual 3.0T startup rattle. I'd get it to a shop sooner than later.
Valpo A7
02-16-2021, 04:18 AM
Mine had the startup rattle when we purchased at 142,000 but I did not know about it at the time since it was hot out and the dealer started the car before we looked at it to start drawing down the heat in the car. Once I realized it was there I initially just thought it was 142,000 mile old lifters pumping up from cold. Fast forward to about 180,000 when it through the timing codes. Indy shop looked at it and told me it was probably the chains. More research and other testing I happened but the car ran perfect and gave no indication of timing problems. At 204,xxx it was time to go get smog test and the codes made it fail. At that point researched the process to get the engine out. Once out the chains are fairly simple. I think it took me less than 2 hours once the chains were exposed. Then it was time to reassemble. Pulling the engine took longer than expected and full disclosure this was my very first EVER engine pull but I knew I had my dad to help who was a 35 year veteran mechanic. He helped get the engine out but going back in was all me and I just took my time. Thanks to Covid I work from home and did not need my car so I did not rush putting it back together.
If you were to pay a shop to do this a seasoned mechanic will take probably 5-6 days start to finish.
AtmosphereA7
02-16-2021, 12:42 PM
Most of the time it's the upper tensioners, which can be replaced without removing the engine.
430hps4
02-16-2021, 03:07 PM
How many miles on yours, don't be shy, it helps explain the issue.?
I'm at 133k now
xanmato
02-16-2021, 07:58 PM
Unfortunately mileage does not matter, and even worse is that this is a fundamental design flaw, even the updated tensioners can fail.
My car started rattling at..... 20k. I have the updated tensioners. To really scratch your brain: I would have never known until the pandemic allowed me to work from home and my car sat for over a week. Anyone who drives their car everyday may never notice that their tensioners are technically failing. As long as I go out and start my car every 4 days or less, I don't have a startup rattle.
What's bad news for OP is that it seems like his tensioners can barely hold any oil pressure as is, or something else has gone wrong.
Valpo A7
02-17-2021, 06:20 AM
Damage I found when I pulled my engine for the timing chain repairs.
Cam tensioner driver side
220375
Stretched chains
220376
Chain chewed the tensioner
220377
Upper plastic piece between the 2 cams
220378
Side guide on the driver side tensioner
220379
Compete look at the chains
220380
Alabama
02-17-2021, 09:03 AM
Damage I found when I pulled my engine for the timing chain repairs.
Compete look at the chains
220380
The silver lining is that the repair gave you a great Avatar!
christianb5s4
02-18-2021, 10:30 AM
I will say that on my C6.5 with the gen1 3.0T, I've had intermittent rattle for the entire 3 years I've had the car. It happens with no rhyme or reason and on occasion it'll rattle longer, sometimes shorter, but has never created issues that I can tell.
The warm start rattle is concerning however. Have you used VCDS to see if there are any timing related codes?