Engine knocking during cold start

[gunzie]

Hi,

Seems like many people are having this problem and the dealers don't know what it is or how to approach the problem. My noise is less then before now after changing the air filter and spark plugs, but its still there.

I think we should contact Porsche directly before our engines fail, especially when they're out of the warranty period. Maybe we should start a online petition.

www.petitiononline.com

Did your engines sound like this?

Mine is going in on the 18th; I'll report back after that.

[cayenne69]

Thanks for your reply,

Please look at my video on

Everyting is normal, but after 30 secs to about 4 minutes you think the engine will die right in front of you. If I start the car and drive right away we cant notice this sound and have no hesitation, except if I stop at a red light for example between the range of 30 secs to 4 minutes depending on temperature.

Please dont hesitate to comment,

Thanks,

GUY

[wvicary]

What weight/type of engine oil are you using? It still sounds like the lower timing chain tensioner to me.

[cayenne69]

What weight/type of engine oil are you using? It still sounds like the lower timing chain tensioner to me.

Changed coils pack, spark plug and air filter and it's not better. Got also a couple of misfire cy1 and cyl 5 on durametric. Using always Mobil1 0W40 as recommended for the V6. But I don't know why it's only at warmup and idle. When driving even cold the engine sounds like a new one.

I have a clue for a vaccum leak related on something operating at warmup. When the engine is warm I can't hear anything.

Thanks for helping me.

[wvicary]

The reason I mentioned the tensioner is that your engine is a version of the VW VR6 and that noise sounds very close to the noise caused when the tensioner looses oil pressure from sitting over night or even a few hours sometimes. If you have a vacuum leak then I suggest finding a garage with a smoke tester as they should be able to locate the leak in a matter of minutes.

On the VW engine the tensioner can be changed easily, it just threads into the side of the rear timing chain cover.

[cayenne69]

The reason I mentioned the tensioner is that your engine is a version of the VW VR6 and that noise sounds very close to the noise caused when the tensioner looses oil pressure from sitting over night or even a few hours sometimes. If you have a vacuum leak then I suggest finding a garage with a smoke tester as they should be able to locate the leak in a matter of minutes.

On the VW engine the tensioner can be changed easily, it just threads into the side of the rear timing chain cover.

Thank you very much for the info. I'm not very familar to open the timing chain cover, if you or any members can share pictures, diagram or more tips to do job perfectly.

:clapping:

[wvicary]

You don't have to remove the timing chain cover, the tensioner threads into the housing and thats all you have to remove. I'll try and post a pic later.

[wvicary]

It's item 11 in the attached pic. It's just unthreads from the timing chain cover and it's located on the R/Rear of the engine under the intake manifold area.

[cayenne69]

It's item 11 in the attached pic. It's just unthreads from the timing chain cover and it's located on the R/Rear of the engine under the intake manifold area.

Thanks for helping me, it's really appreciated. I sent this video to porsche dealer, spoke with many specialized people and NO one else was able to find the problem. What you told me is very logical, because when the engine is cold the upper tensioner is loose and knoking and when oil pressure slowly come into the hydrolic tensioner (probably defect and slow to react) the noise come off slowly. This also explain the misfire on cyl 1 and cyl 5 because the loose chain may disturb the timing a little bit during the warmup.

I just want to know when I'll replace this part, if I need to secure the timing chain or I can safely just change the "bolt" without droping a guide or a rail in the bottom of the case. I probably need also to bleed the part with oil before replace it with a new o ring.

Thank you very much, I was trying to resolve this since two year and I think I'm very close to tell you... You are the best.

[wvicary]

When you remove the tensioner nothing will move or become dislodged, just don't turn the engine over with the tensioner loose or removed. The old tensioners wear and loose their oil charge when sitting for a time and then it needs to bleed and refill with oil. The new unit will self bleed but it may take a few minutes for this to occur.

[etaxelson]

Have bad news for all your Cayenne's with the ticking sound...you have a scored cylinder wall. Mine in at the dealer right now waiting for Porsche NA to weigh in on a replacement. Will keep you posted - please let me know what conclusions everyone has come to with their vehicle.

Thanks!

[armitagecayenne]

Hi 97boxsterred...Pls post the video again....it have been removed...u can send to armitage09@yahoo.com.

mine a 2005 v6, have a 'boom boom' sound during cold start too.

Just install the K&N filter...it sound like a turbo car sucking in air when i press hard on the gas pedal...sooo nice.

Any spark plug recommendation?...NGK?

thx

[SA321]

Have bad news for all your Cayenne's with the ticking sound...you have a scored cylinder wall. Mine in at the dealer right now waiting for Porsche NA to weigh in on a replacement. Will keep you posted - please let me know what conclusions everyone has come to with their vehicle.

Thanks!

There are quite a few people with this problem on V8T on other forum with some ugly pictures. Does your car have other problems like excessive oil consumption? If not how did u manage to convince Porsche to look at engine replacement?

[hitz]

Hi, my 2003, 53 cayenne s In uk.

started to jerk while picking up then after a few weeks it started to jerk and shake, almost like its about to stall. ( have the same knocking noise too).

It had a service incl spark plug replacement winter 2009. Well 2 weeks ago i got it into porsche and they replaced 2 coil packs, it seemed to solve it but 2 days ago its all started again.the shakes and knocking seems louder.

Im not that clued up with all this and have checked through some of the threads in these forums.

Has anyone cured these probs without having to replace the engine?

could it be anything to do with cam sensors? as once a friend with some plug in diagnostic tool got 2 fault codes, i think they were p0011 and other fault was maybe p0021(not 100% sure) but on checking it did say something P0011: Camshaft position Timing over.

any suggestions????? :help:

Edited June 21, 2010 by hitz

[Bcheney]

On a 2008 Cayenne base V6 Direct Injection engine  the cold start noise mentioned in this topic remains even though the tensioner has been replaced. If you key bump the Ignition 3 or 4 times (turn the key on/off without allowing the engine to fire) and then fully turn the ignition key the 5th time the engine starts and doesn't make the noise. It seems that the engine is building just enough oil pressure to provide adequate lubrication. Can't seem to figure out how to solve the symptom noise outside of key bumping the ignition. I found some information via a Porsche tech that says the oil pump gets its intitial supply of oil at cold start from a small reservoir behind the oil pump. There is a "pressure piston" that can be removed from the oil pump externally but we haven't tried to do that yet. Although the pressure piston is a separate part...the part doesn't carry a unique part number that can be found anywhere online or with a local Porsche dealer parts department. Does anyone have any information that could help to solve this problem? The graphics from the Porsche technical resource called the SIT are included for your reference below.

 

**Well it seems that including the images from the SIT is out of bounds...in this forum. 

 

 

 

 

 

 

Edited November 2, 2017 by Bcheney
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