996 Turbo / GT2 Turbo discussion on previous model 2000-2005 Porsche 911 Twin Turbo and 911 GT2.

Knocking noise at Idle - Bad Oil Pump?

Thread Tools
 
Search this Thread
 
Rate Thread
 
  #16  
Old 01-29-2010 | 08:08 AM
PAULUNM's Avatar
Registered User
Joined: Mar 2007
Posts: 560
From: Los Angeles, Ca
Rep Power: 45
PAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to all
Originally Posted by raineycd
Was it jhaung's oil pump that failed or something else - going from memory...
I was thinking of a different member...

I think Jhuang was pushing 600+ hp, there was some odd timing issue just before his motor popped...
 
  #17  
Old 01-29-2010 | 08:09 AM
PAULUNM's Avatar
Registered User
Joined: Mar 2007
Posts: 560
From: Los Angeles, Ca
Rep Power: 45
PAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to all
Originally Posted by adeeois
Some cars are noisier than others. My buddy's 02 is much louder than my 01. IMS shaft problems are mostly related to naturally aspirated 996's not turbos. I've completely rebuilt my engine and believe me you don't want to go there unless your forced to.
Why did you rebuild your motor?
 
  #18  
Old 03-08-2010 | 02:55 PM
PAULUNM's Avatar
Registered User
Joined: Mar 2007
Posts: 560
From: Los Angeles, Ca
Rep Power: 45
PAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to all
Originally Posted by iceman153
Not a bad idea, I should definitely take it by and get a second opinion of the noise.
Iceman- Did you have Kevin look at your car?
 
  #19  
Old 03-08-2010 | 06:15 PM
heavychevy's Avatar
Registered User
Joined: Jul 2006
Posts: 8,934
From: ga
Rep Power: 551
heavychevy Is a GOD !heavychevy Is a GOD !heavychevy Is a GOD !heavychevy Is a GOD !heavychevy Is a GOD !heavychevy Is a GOD !heavychevy Is a GOD !heavychevy Is a GOD !heavychevy Is a GOD !heavychevy Is a GOD !heavychevy Is a GOD !
I'd like to see how many motors have actually blown up. Up until Tom Kerr's a couple of years ago, a blown TT motor was like a big foot sighting.

Now that we have tuners poppoing up out of the wood works, they seem more common but still very rare. Have even one of them been a car with stock Turbos and a tune?

This is getting to be a pandemic with all these posts.
 
  #20  
Old 03-08-2010 | 07:10 PM
Hogapalooza's Avatar
Registered User
Joined: Nov 2009
Posts: 1,184
From: Bentonville, AR
Rep Power: 87
Hogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond repute
I have only had my car since ROctober 09. I heard this clanky, rattle, vibration sound the first time it was fired up after it was delivered. I thought it was in the muffler. It scared the crap out of me when the guy changing my oil told me he thought it was from the timing chain area. He scoped it and could only tell me where the noise was coming from but not what it was. In fact he said it could be from another part of the engine and just coming out at the point he was hearing it.
I've put almost 8,000 miles of the car, the noise is still there. It isn't as bad now that I've put Lucas heavy duty oil treatment in the car.
I hate the dam noise! It makes the car sound cheap! BUT it seems to be normal. If any of these owners are new like I am then it's probably is just a normal Porsche 996 TT sound that a regular car owner doesn't expect to hear.
 
  #21  
Old 03-08-2010 | 07:30 PM
VAGscum's Avatar
Registered User
Joined: Oct 2008
Posts: 1,696
From: Portland Oregon
Rep Power: 187
VAGscum Is a GOD !VAGscum Is a GOD !VAGscum Is a GOD !VAGscum Is a GOD !VAGscum Is a GOD !VAGscum Is a GOD !VAGscum Is a GOD !VAGscum Is a GOD !VAGscum Is a GOD !VAGscum Is a GOD !VAGscum Is a GOD !
On my Audi I used to get excessive valvetrain noise with Mobil 1 oil. I switched to another type of synthetic and the noise went away. Mobil 1 changed their formula several years ago and it hasn't been the same since. Maybe try another 100% synthetic like Elf or Motul and see if the noise goes away. If some engines are noisier than others it could also mean some engines react differently to Mobil 1 than others.
 
  #22  
Old 03-08-2010 | 08:04 PM
Hogapalooza's Avatar
Registered User
Joined: Nov 2009
Posts: 1,184
From: Bentonville, AR
Rep Power: 87
Hogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond repute
Originally Posted by VAGscum
On my Audi I used to get excessive valvetrain noise with Mobil 1 oil. I switched to another type of synthetic and the noise went away. Mobil 1 changed their formula several years ago and it hasn't been the same since. Maybe try another 100% synthetic like Elf or Motul and see if the noise goes away. If some engines are noisier than others it could also mean some engines react differently to Mobil 1 than others.
I will do just that, in fact I may change my oil early just to try it. What weight do you use? 5-30, 10-30, ?
 
  #23  
Old 03-08-2010 | 10:32 PM
PAULUNM's Avatar
Registered User
Joined: Mar 2007
Posts: 560
From: Los Angeles, Ca
Rep Power: 45
PAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to all
Kevin from UMW recommends Mobil 1 5 W 50. Hard to find, but if Kevin is a fan...

I just switched to it for my first oil change since I bought the car. It had M1 0 W 40 in it, and no difference in noise since the change.

I understand the noise at idle is from the timing chain, so I can't imagine a different oil would quiet it at all...
 
  #24  
Old 03-08-2010 | 10:57 PM
iceman153's Avatar
Thread Starter
|
Registered User
Joined: Jan 2010
Posts: 41
From: Vancouver, BC
Rep Power: 16
iceman153 is infamous around these parts
I have since talked to kevin about the car and taken it to a well respected local indy mechanic as well as the local porsche dealer. Everyone that's heard it has said it sounds pretty normal for this car, mine may be a touch higher than the average, but both said they had heard quite a few that were louder, and both had never seen an intermediate shaft actually fail.

Kevin hasn't listened to my car, but he did say that the ones he has seen fail the noise will get significantly louder over time, and will eventually change into a continuous whirring kind of a noise and you'll see engine warning lights show up. At that point it's just a matter of time.

Like most others on the forums i've spent a while researching oils and the Mobil1 0w40 has changed in formulation, i believe the zinc content was reduced. Mobil1 also has a 5w50 oil that is porsche approved that's formulation hasn't changed at all, unfortunately it's hard to find in the US, it's available in canada at walmart or canadian tire. You can get it online here :
http://store.avlube.com/mobil15w50.html
I ordered 3 cases which is just enough for 2 changes, shipping was fast, i've seen better packaging, but it arrived ok.

The 5w50 is means a little bit thicker oil at operating temp which is where we hear the noise to hopefully quieten it down, and it still flows well at low temps. I'd be concerned using anything above a 5w rated oil as it can cause pre-mature wear in the turbos.

As for oil additives, almost everyone I've asked, specially Kevin said to steer clear of them. If they improved the oil's performance or anti-wear then mobil1 would add it into their oils, and/or porsche would recommend the additives. Don't trust your $30,000 motor to $5 oil additives is basically what kevin said He also recommended the Mobil1 5W50.

Besides the oil change about all we can do is at each change get an oil sample analysed for metal content, and be sure to pull apart your oil filter looking for metal fragments. Those are really the only solid indications of engine wear. If you find anything it may well be a good time to go get an aftermarket warranty

That's about everything i've learnt, along with art's recent post with photos of his engine I'm pretty confident there aren't any issues with the car, just an annoying rattle that you'll have to learn to love!
 
  #25  
Old 03-09-2010 | 06:37 AM
Hogapalooza's Avatar
Registered User
Joined: Nov 2009
Posts: 1,184
From: Bentonville, AR
Rep Power: 87
Hogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond reputeHogapalooza has a reputation beyond repute
Thanks for the info. I understand what Kevin is saying about additives but each company has a diferent philosophy on what is good and what is acceptable profit wise in the production of their product. So to think Mobil1 would have the perfect product seems a strectch to me. But the info is dully noted and I'll do more research on the oil I use in my next oil change as it is coming up soon.
Has anyone noticed a diference between the summer and winter months? If you change your oil to a thinner/thicker type depending on the season, was there a noticable change in the noise? Or do most of you run the same year around, for those that drive more then 1 season.
 
  #26  
Old 03-09-2010 | 07:25 AM
IMA Motorsport's Avatar
Former Vendor
Joined: Jan 2010
Posts: 253
From: Virginia
Rep Power: 0
IMA Motorsport is infamous around these partsIMA Motorsport is infamous around these parts
Other experience

Hope that our experience can also shed some light. We have seen in 2 engines that we repaired a noise that would come on just over idle rev's. After doing some checking of the engine we determined it was chain related. After looking into it further engine still in car we discovered that the chain gear on the intermediate shaft was beating the woodruff key loose and damaging the groove for the key.
As the sprocket slides on the intermediate shaft this can possibly happen. We have had quite a few race GT3RS and RSR motors apart throughout the years and decided to use the shaft from these engines as it is all one piece. They are bullet proof.
Our first case the customer and myself were pretty insistent on the fact that the motor should of not been making noise and that is what lead us to identify the source. Sometimes you need to make sure of the source and not just say its normal. IMO
Hope this helps.
 
  #27  
Old 03-09-2010 | 09:11 AM
PAULUNM's Avatar
Registered User
Joined: Mar 2007
Posts: 560
From: Los Angeles, Ca
Rep Power: 45
PAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to allPAULUNM is a name known to all
Originally Posted by IMA Motorsport
Hope that our experience can also shed some light. We have seen in 2 engines that we repaired a noise that would come on just over idle rev's. After doing some checking of the engine we determined it was chain related. After looking into it further engine still in car we discovered that the chain gear on the intermediate shaft was beating the woodruff key loose and damaging the groove for the key.
As the sprocket slides on the intermediate shaft this can possibly happen. We have had quite a few race GT3RS and RSR motors apart throughout the years and decided to use the shaft from these engines as it is all one piece. They are bullet proof.
Our first case the customer and myself were pretty insistent on the fact that the motor should of not been making noise and that is what lead us to identify the source. Sometimes you need to make sure of the source and not just say its normal. IMO
Hope this helps.
Would you say that the noise is "abnormal" if it is only apparent at revs above idle? What about a noise that is apparent at idle, but goes away off idle?

Also, would you see metal particles in the oil or filter if the chain gear is scoring the woodruf key (whatever that is...)?
 
  #28  
Old 03-09-2010 | 04:25 PM
iceman153's Avatar
Thread Starter
|
Registered User
Joined: Jan 2010
Posts: 41
From: Vancouver, BC
Rep Power: 16
iceman153 is infamous around these parts
Hey Ivan, the more common noise that people complain of exists at idle, and goes away just over idle rev's. Note i do hear it come back at around 2,000rpm and it goes away again above that. Sounds slightly different to what you described?
 
  #29  
Old 03-09-2010 | 05:27 PM
IMA Motorsport's Avatar
Former Vendor
Joined: Jan 2010
Posts: 253
From: Virginia
Rep Power: 0
IMA Motorsport is infamous around these partsIMA Motorsport is infamous around these parts
Noise

One thing to consider that is occurring at idle and off, lets say blipping throttle slightly as the chain and tensioner have a bit of slap and movement because of the valve movement at low engine speeds. Cam lobes hitting lifters, it is a bit uneven. Once off idle at higher revs the valve train and chain sort of stabilize and the tensioners are steadier less chain movement, so if you had a problem in this area it could manifest itself randomly at idle or slight throttle movement. The noise that I heard does not belong there. It sounded like a very lite tap or rattle. Very subtle but evident of a problem.

No metal in oil. Reason being is that the shaft appeared to be soft and allowing the key to move in the groove creating play. Axial play. It's like the groove might of been a bit larger than key or key smaller than groove. Improper tolerance is the only explanation or the metallurgy in the shaft was not heat treated properly.

Not saying that is your problem but the first car that came in with this noise was a pain to pin point because you do not want to go in the engine without direction. We took our time and removed as much as we could and ran the engine without the valve cover and there it was when the engine was not running we could move the chain back and forth and saw the sprocket moving.

Hope this helps. Let me know if I can assist further.
 
  #30  
Old 03-09-2010 | 07:25 PM
adeeois's Avatar
Registered User
Joined: Aug 2006
Posts: 108
From: Sylvania Ohio 43560
Rep Power: 23
adeeois is infamous around these parts
Originally Posted by PAULUNM
Why did you rebuild your motor?
Sorry it's taken so long for a reply. Bent rod #4. It was just hitting the crank counter balance enough to make a ticking noise at cold start up. The noise went away after warm up likely due to thermal expansion. Head gasket showed a slight fracture at #4 cylinder. We think the bend was the result of a hydrolock type condition or possibly a mechanical over rev. Here's a kicker, touch the clutch and the noise would disappear. Why? The crank was moving just enough to eliminate the interference. Intermediate shaft was fine (40,000 miles). However the IMS bolts had very little holding tension. My mechanic went with a higher grade bolt and slightly more torque with lock-tite. Installed all new bearings, Pauter rods, all new intake lifters, and ARP studs along with the usual parts list. Possible big HP build down the road.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
eclip5e
Automobiles For Sale
8
04-28-2022 12:38 AM
nlakind
Automobiles For Sale
3
11-06-2015 10:15 AM
orbelo
996 Turbo / GT2
30
08-30-2015 12:26 PM
porsche42
991
0
08-28-2015 06:53 PM
The Oss
Automobiles For Sale
2
08-24-2015 08:19 PM



You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Knocking noise at Idle - Bad Oil Pump?



All times are GMT -6. The time now is 09:29 AM.