# Rattle sound when starting **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** toyota\ **Created:** [December 22, 2020, 5:47am UTC](https://community.cartalk.com/t/rattle-sound-when-starting/173531 "2020-12-22T05:47:35Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![redneckred](https://avatars.discourse-cdn.com/v4/letter/r/50afbb/32.png) [@redneckred](https://community.cartalk.com/u/redneckred)\ **Post date:** [December 22, 2020, 5:47am UTC](https://community.cartalk.com/t/rattle-sound-when-starting/173531/1 "2020-12-22T05:47:35Z")
I am posting this for a friend - she has an older (think it was a 2010) Camry. Most of the time, from a cold engine start in the morning, when she starts the motor she hears a rattle/clank noise for a few seconds that stops. It will repeat itself sometimes during the day when it is started again, but not always. She has tried using an oil treatment for a possible lifter noise, she has replaced the starter and noted the car starts better, but the rattle/clank noise continues on cold starts. She has heard/researched on the net that this is possibly a cam gear that is bent/going bad. Anyone have any ideas on this? ---
**Author:** ![Barkydog](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/barkydog/32/2470_2.png) [@Barkydog](https://community.cartalk.com/u/Barkydog)\ **Post date:** [December 22, 2020, 5:55am UTC](https://community.cartalk.com/t/rattle-sound-when-starting/173531/2 "2020-12-22T05:55:10Z")
I had a similar situation, it ended up being a bad bearing in the tensioner, Proper diagnosis for a proper repair. ---
**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\ **Post date:** [December 22, 2020, 12:07pm UTC](https://community.cartalk.com/t/rattle-sound-when-starting/173531/3 "2020-12-22T12:07:26Z")
It almost sounds like a rod bearing knock that goes away when the oil pressure hits. Hopefully she has checked the motor oil level. Without hearing the noise it’s near impossible to be definitive but a rattle/clank that goes away right after startup often points to a rod bearing noise. ---
**Author:** ![ledhed75](https://avatars.discourse-cdn.com/v4/letter/l/f6c823/32.png) [@ledhed75](https://community.cartalk.com/u/ledhed75)\ **Post date:** [December 22, 2020, 12:11pm UTC](https://community.cartalk.com/t/rattle-sound-when-starting/173531/4 "2020-12-22T12:11:47Z")
Could also be a loose heat shield in the exhaust system somewhere. Once it warms up, the metal expands and rattle stops. ---
**Author:** ![redneckred](https://avatars.discourse-cdn.com/v4/letter/r/50afbb/32.png) [@redneckred](https://community.cartalk.com/u/redneckred)\ **Post date:** [December 22, 2020, 3:18pm UTC](https://community.cartalk.com/t/rattle-sound-when-starting/173531/5 "2020-12-22T15:18:33Z")
I know she has checked the oil level and has recently had it changed. ---
**Author:** ![redneckred](https://avatars.discourse-cdn.com/v4/letter/r/50afbb/32.png) [@redneckred](https://community.cartalk.com/u/redneckred)\ **Post date:** [December 22, 2020, 3:19pm UTC](https://community.cartalk.com/t/rattle-sound-when-starting/173531/6 "2020-12-22T15:19:17Z")
Are you referring to the timing tensioner or the serpentine tensioner? ---
**Author:** ![redneckred](https://avatars.discourse-cdn.com/v4/letter/r/50afbb/32.png) [@redneckred](https://community.cartalk.com/u/redneckred)\ **Post date:** [December 22, 2020, 3:19pm UTC](https://community.cartalk.com/t/rattle-sound-when-starting/173531/7 "2020-12-22T15:19:54Z")
I forget about the heat shield, somewhere to check. ---
**Author:** ![Barkydog](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/barkydog/32/2470_2.png) [@Barkydog](https://community.cartalk.com/u/Barkydog)\ **Post date:** [December 22, 2020, 5:10pm UTC](https://community.cartalk.com/t/rattle-sound-when-starting/173531/8 "2020-12-22T17:10:18Z")
I was referencing the serpentine belt tensioner. ---
**Author:** ![Nevada\_545](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nevada_545/32/41232_2.png) [@Nevada\_545](https://community.cartalk.com/u/Nevada_545)\ **Post date:** [December 22, 2020, 5:37pm UTC](https://community.cartalk.com/t/rattle-sound-when-starting/173531/9 "2020-12-22T17:37:15Z")
Knocking noise from the variable valve timing gear during start-up is a common problem on the 4 cylinder engine. The engine oil drains from the lobes inside the gear creating a void and results in a knocking noise during start-up. > **[SB-10061557-2280.pdf](https://static.nhtsa.gov/odi/tsbs/2013/SB-10061557-2280.pdf)** > > 2.24 MB