991.2 Engine tapping noise after cold start
#31
Perhaps even 5w-50 will slow down the oil drain from the lifters to make a difference. It seems 4-5 days between starts is when I noticed it tapping where as 3 days or less seems to be okay.
#32
Since I got the 911, my wife has started driving the C63 AMG. After a couple of months of driving, she started noticing the ticking noise on startup. Took it to the dealer and they thought that the lifters had failed. However, the noise is very common in the AMG and there is a protocol that they follow before repair. Basically it's running the car at high revs. The service manager told me that this is to "reset" the lifters. Basically it happens because the engine isn't being driven hard enough. My wife drives in auto and basically it's shifting around 2500 and she does a lot of short drives. The service manager states that this can make the lifters stick.
I don't know enough about engines to wether this is true or not. Can someone with more knowledge confirm this? BTW, the ticking did go away.
I don't know enough about engines to wether this is true or not. Can someone with more knowledge confirm this? BTW, the ticking did go away.
#33
If it taps all the time Porsche will fix it for sure no question. The big question is whether my car is deemed bad enough for Porsche to decide on repair or not at this point.
#34
I'm sure Porsche corporate wouldn't be too pleased to hear their employees telling you stuff their own engineers don't approve of.
#37
Update - so car was parked at the the dealer for 6 days, started the car with service manager and shop foreman present, and it tapped for 15 minutes at which point we turned off. The shop foreman acknowledge that it sounded to be from the lifter. Also started another car in their lot to compare and it was not tapping at all. Got it all on video.
Dealer will be reporting to Porsche - awaiting their decision.
Last edited by LC991.2; 04-25-2017 at 05:49 PM.
#38
If all new Porsche engines have this tapping lifter then I would say it's normal but if yours or my car is 1 out 10 or even 1 out of 5 then there must be problem with lifter or lubrication system with our car.
#39
This is the third time I've had the engine control fault light come on but I don't think this is related to lifter tapping. Last 2 times error code was generated from emission control system.
Update - so car was parked at the the dealer for 6 days, started the car with service manager and shop foreman present, and it tapped for 15 minutes at which point we turned off. The shop foreman acknowledge that it sounded to be from the lifter. Also started another car in their lot to compare and it was not tapping at all. Got it all on video.
Dealer will be reporting to Porsche - awaiting their decision.
Update - so car was parked at the the dealer for 6 days, started the car with service manager and shop foreman present, and it tapped for 15 minutes at which point we turned off. The shop foreman acknowledge that it sounded to be from the lifter. Also started another car in their lot to compare and it was not tapping at all. Got it all on video.
Dealer will be reporting to Porsche - awaiting their decision.
#40
5w-40 is the *wrong* way to go to possibly address this tapping noise at cold start.
The better oil would be 0w-40. The "0w" representing a lower cold temperature viscosity with (probably) better cold flow characteristics.
The 0w-40 oil would thus (again probably) flow better at cold start and afterwards but the tapping noise is not really due to lack of oil flow.
It is air in one or more lifters.
The better oil would be 0w-40. The "0w" representing a lower cold temperature viscosity with (probably) better cold flow characteristics.
The 0w-40 oil would thus (again probably) flow better at cold start and afterwards but the tapping noise is not really due to lack of oil flow.
It is air in one or more lifters.
#41
As a side note, newer engines run lower oil pressures to reduce parasitic drag and improve fuel mileage and horsepower. Porsche brags about the "on demand" electronic oiling system these cars have. I wonder if that contributes to this problem? My neighbor has a 2006 997 with the M97 engine and it pegs the oil pressure gauge on startup and rarely drops below 3. It is a much quieter running engine (but he's had more issues with oil leaks!!). My oil pressure never goes that high. Maybe it's a tradeoff. High oil pressure equals quiet valvetrain but lots of oil leaks and vice versa. Also, my Mercedes AMG CLS55 had the same noisy lifter issue.
#43
Update - so car was parked at the the dealer for 6 days, started the car with service manager and shop foreman present, and it tapped for 15 minutes at which point we turned off. The shop foreman acknowledge that it sounded to be from the lifter. Also started another car in their lot to compare and it was not tapping at all. Got it all on video.
Dealer will be reporting to Porsche - awaiting their decision.
#44
There's something to be said for this. I've occasionally heard (light) ticking from my 3.4L engine, and it's always, without exception, gone away after an Italian tuneup. I've always assumed the ticking was the high-pressure DFI system, though, not lifters. It's never been loud enough to be a concern.
If my car were making as much racket as some of the videos we've seen, my strategy would be to let it warm up thoroughly and then thrash the hell out of it. The idea would be to either fix the problem or force a catastrophic failure that the dealer can't answer with the usual "They all do that" BS.
If my car were making as much racket as some of the videos we've seen, my strategy would be to let it warm up thoroughly and then thrash the hell out of it. The idea would be to either fix the problem or force a catastrophic failure that the dealer can't answer with the usual "They all do that" BS.
#45
Here is my take.
It appears you will be getting some relief from Porsche. Hope so.
I think you have to look at the landscape here. I mean no disrespect here but, Porsche have created parts changers at best. From the SA to the tech's, they have to log in on any car and tell Porsche what they are doing. Porsche then advises them on what and how to do it. I'm sure there are some very clever people working , but if they are not allowed to think for themselves, what hope do we have.
In this case, I think there was some distance between the noise heard and what is expected to be normal. It seems that once the car was left at the dealer the time and scope of the noise was understood.
I think some good advice has been given and some really bad advice has been given. Do not add any sort of additive in the oil and do not change the oil weight other than what is in the owners manual.
The additive I suspect is some sort of anti wear additive to hopefully stop any wear from happening with excessive lash. First off, this stuff messes with your cat and secondly, a loose lash will not harm the camshaft base or follower. There is a designed amount of gap between the camshaft and the follower for oil to be present.
Oil weight plays a huge role in the engines performance and reliability. With today's mileage standards and emissions, lighter oil is required. Oil pressures are lower to help with performance. It takes a lot of the engines performance to push oil through the system at high pressure. With lower pressures comes tighter oil clearances. The bearing surfaces are rock hard as well for life span. The greatest amount of damage an engine can see from normal use is on startup. You run thicker "winter weight" oil and the oil film between the crankshaft and the bearings will not be there.
Also, the variable valve control is a function of the oils viscosity as well. Changing the oil will effect the valve timing.
A noisy follower is not normal and should never be heard. The oil is trapped in the system once the engine is stopped. The relief valves should close and the oil cannot find it way back. This holds oil in the oil galleys. However the oil has only one path in and out of the follower. The oil galley in the head to feed the follower is on the top side facing upwards. The oil would have to drain up against gravity to escape the follower. Difficult to imagine this happening. And its only way to escape is through the clearance between the follower and the head, which is less than 0.001" on each side.
The follower will collapse the same amount as the cam lift. At this point there is still some head room in the follower before it bottoms out. So oil will always be present in the follower. The cam lobe doesn't squeeze all of the oil out.
You sir have a failing follower that is leaking oil through its retainer sealing system inside that follower. This is happening even when the engine is up to running temps and pressure. The pressure is overcoming the leak, but the leak is allowing the oil to escape through the seal in the follower. This is on the bottom side facing the valve.
This is something of an old wife's tale that followers make noise. Even the dealer appears to be believing this still. The reason is, they don't understand how these engines are designed today as they never get to see inside of them. If they did, they would know its not possible and they would see all of the new ideas used to help with mileage and emissions.
Good luck and demand that the noise in investigated and not left to some old wife's tale. Arm yourself with knowledge. Knowledge trumps a wife's tale every time.
It appears you will be getting some relief from Porsche. Hope so.
I think you have to look at the landscape here. I mean no disrespect here but, Porsche have created parts changers at best. From the SA to the tech's, they have to log in on any car and tell Porsche what they are doing. Porsche then advises them on what and how to do it. I'm sure there are some very clever people working , but if they are not allowed to think for themselves, what hope do we have.
In this case, I think there was some distance between the noise heard and what is expected to be normal. It seems that once the car was left at the dealer the time and scope of the noise was understood.
I think some good advice has been given and some really bad advice has been given. Do not add any sort of additive in the oil and do not change the oil weight other than what is in the owners manual.
The additive I suspect is some sort of anti wear additive to hopefully stop any wear from happening with excessive lash. First off, this stuff messes with your cat and secondly, a loose lash will not harm the camshaft base or follower. There is a designed amount of gap between the camshaft and the follower for oil to be present.
Oil weight plays a huge role in the engines performance and reliability. With today's mileage standards and emissions, lighter oil is required. Oil pressures are lower to help with performance. It takes a lot of the engines performance to push oil through the system at high pressure. With lower pressures comes tighter oil clearances. The bearing surfaces are rock hard as well for life span. The greatest amount of damage an engine can see from normal use is on startup. You run thicker "winter weight" oil and the oil film between the crankshaft and the bearings will not be there.
Also, the variable valve control is a function of the oils viscosity as well. Changing the oil will effect the valve timing.
A noisy follower is not normal and should never be heard. The oil is trapped in the system once the engine is stopped. The relief valves should close and the oil cannot find it way back. This holds oil in the oil galleys. However the oil has only one path in and out of the follower. The oil galley in the head to feed the follower is on the top side facing upwards. The oil would have to drain up against gravity to escape the follower. Difficult to imagine this happening. And its only way to escape is through the clearance between the follower and the head, which is less than 0.001" on each side.
The follower will collapse the same amount as the cam lift. At this point there is still some head room in the follower before it bottoms out. So oil will always be present in the follower. The cam lobe doesn't squeeze all of the oil out.
You sir have a failing follower that is leaking oil through its retainer sealing system inside that follower. This is happening even when the engine is up to running temps and pressure. The pressure is overcoming the leak, but the leak is allowing the oil to escape through the seal in the follower. This is on the bottom side facing the valve.
This is something of an old wife's tale that followers make noise. Even the dealer appears to be believing this still. The reason is, they don't understand how these engines are designed today as they never get to see inside of them. If they did, they would know its not possible and they would see all of the new ideas used to help with mileage and emissions.
Good luck and demand that the noise in investigated and not left to some old wife's tale. Arm yourself with knowledge. Knowledge trumps a wife's tale every time.
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