Periodic engine "rattle" at start up
#1
Periodic engine "rattle" at start up
Through my experiences over the years, with different vehicle brands with chain driven overhead camshafts, I heard this type of noise in almost all of them. Never made me think too much of, until now, with our 991's being more expensive to repair than my 175,000 mile Kia SUV (which never developed any problems, since hearing this noise within months of purchasing it new).
The noise I "think" I am hearing is one of the timing chains coming up to tension, as oil pressure builds upon engine start up. I've briefly spoken to a Porsche certified mechanic to confirm that the 991 does employ hydraulic tensioners that can bleed off over time, once the engine has shut down. I don't hear this all of the time, even when the engine has been shut down for more than a few days. Perhaps the bleed off is dependent upon "where" the crankshaft ends up at shut down.
While still under warranty, I plan on bringing the car to the dealer for inspection and to get this on record (2016 Targa GTS, 15k miles, owned for a year).
I am just curious if anyone else has heard this same noise and if you brought it into the dealer to be inspected. Was this considered "normal" and no cause for alarm or long term effect? Or was a defect found, requiring maintenance and/or repair?
Thanks - Jim
The noise I "think" I am hearing is one of the timing chains coming up to tension, as oil pressure builds upon engine start up. I've briefly spoken to a Porsche certified mechanic to confirm that the 991 does employ hydraulic tensioners that can bleed off over time, once the engine has shut down. I don't hear this all of the time, even when the engine has been shut down for more than a few days. Perhaps the bleed off is dependent upon "where" the crankshaft ends up at shut down.
While still under warranty, I plan on bringing the car to the dealer for inspection and to get this on record (2016 Targa GTS, 15k miles, owned for a year).
I am just curious if anyone else has heard this same noise and if you brought it into the dealer to be inspected. Was this considered "normal" and no cause for alarm or long term effect? Or was a defect found, requiring maintenance and/or repair?
Thanks - Jim
#4
What climate do you live in? Same noise in summer vs winter (cold starts)?? Same noise as mile 15 vs your current 15,000 miles??? I assume you're running Mobil 0W40......may want to try A40 approved Mobil 5W50.
#5
South Louisiana. Yes, same noise at 15 and 15,000. Same frequency over those miles as well. Oil viscosity is whatever the dealer replaced it with at oil change.
#6
#7
Through my experiences over the years, with different vehicle brands with chain driven overhead camshafts, I heard this type of noise in almost all of them. Never made me think too much of, until now, with our 991's being more expensive to repair than my 175,000 mile Kia SUV (which never developed an y problems, since hearing this noise within months of purchasing it new).
The noise I "think" I am hearing is one of the timing chains
coming up to tension, as oil pressure builds upon engine
start up. I've briefly spoken to a Porsche certified mechanic
to confirm that the 991 does employ hydraulic tensioners that
can bleed off over time, once the engine has shut down. I don't hear this all of the time, even when the engine has been shut down for more than a few days. Perhaps the bleed off is dependent upon "where" the crankshaft ends up at shut down.
While still under warranty, I plan on bringing the car to the dealer for inspection and to get this on record (2016 Targa GTS, 15k miles, owned for a year).
I am just curious if anyone else has heard this same noise and if you brought it into the dealer to be inspected. Was this considered "normal" and no cause for alarm or long term effect? Or was a defect found, requiring maintenance and/or repair?
Thanks - Jim
The noise I "think" I am hearing is one of the timing chains
coming up to tension, as oil pressure builds upon engine
start up. I've briefly spoken to a Porsche certified mechanic
to confirm that the 991 does employ hydraulic tensioners that
can bleed off over time, once the engine has shut down. I don't hear this all of the time, even when the engine has been shut down for more than a few days. Perhaps the bleed off is dependent upon "where" the crankshaft ends up at shut down.
While still under warranty, I plan on bringing the car to the dealer for inspection and to get this on record (2016 Targa GTS, 15k miles, owned for a year).
I am just curious if anyone else has heard this same noise and if you brought it into the dealer to be inspected. Was this considered "normal" and no cause for alarm or long term effect? Or was a defect found, requiring maintenance and/or repair?
Thanks - Jim
Thanks.
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#9
Possibly. It'll be a challenge to reproduce it, much less catch it in audio/video, whether for here on the forum or for the dealer. Although, it would give me a better shot at presenting this problem, should I happen to catch the sound on video, being it is so sporadic.
I'll see if I can be disciplined enough to remember to start the video rolling BEFORE starting the engine. And if it'll catch the sound from the driver's seat, with the door open.
Thanks for the question (suggestion). I'll post it if I get it.
Jim
I'll see if I can be disciplined enough to remember to start the video rolling BEFORE starting the engine. And if it'll catch the sound from the driver's seat, with the door open.
Thanks for the question (suggestion). I'll post it if I get it.
Jim
#10
what to bring this thread back up.
As i have driven about 3000 miles since i bought the car, i am hearing a rattle/chatter when the car is idling (before the car hit operating oil temp...below 180F)
I know initial cold start (first 2-3 mins) would be loud and normal to be noisy...but even after about 5 mins of local driving, i can hear a rattle/chatter that comes and goes, PDK in D or P doesnt make a diff.
anyone have similar experience? timing tensioner? chain?
Hard to do a video to for the noise because you really have to pay attention to hear it....is gone once the car is warmed up....
As i have driven about 3000 miles since i bought the car, i am hearing a rattle/chatter when the car is idling (before the car hit operating oil temp...below 180F)
I know initial cold start (first 2-3 mins) would be loud and normal to be noisy...but even after about 5 mins of local driving, i can hear a rattle/chatter that comes and goes, PDK in D or P doesnt make a diff.
anyone have similar experience? timing tensioner? chain?
Hard to do a video to for the noise because you really have to pay attention to hear it....is gone once the car is warmed up....
#11
#13
what to bring this thread back up.
As i have driven about 3000 miles since i bought the car, i am hearing a rattle/chatter when the car is idling (before the car hit operating oil temp...below 180F)
I know initial cold start (first 2-3 mins) would be loud and normal to be noisy...but even after about 5 mins of local driving, i can hear a rattle/chatter that comes and goes, PDK in D or P doesnt make a diff.
anyone have similar experience? timing tensioner? chain?
Hard to do a video to for the noise because you really have to pay attention to hear it....is gone once the car is warmed up....
As i have driven about 3000 miles since i bought the car, i am hearing a rattle/chatter when the car is idling (before the car hit operating oil temp...below 180F)
I know initial cold start (first 2-3 mins) would be loud and normal to be noisy...but even after about 5 mins of local driving, i can hear a rattle/chatter that comes and goes, PDK in D or P doesnt make a diff.
anyone have similar experience? timing tensioner? chain?
Hard to do a video to for the noise because you really have to pay attention to hear it....is gone once the car is warmed up....
#14