Noise on cold start - chain tensioner?

My 99 is noisy on a cold startup for literally a fraction of a second, literally, until oil pressure builds. I've read a couple of posts (I think here and elsewhere) saying it's pretty common and (gah) normal(??). Is that true? I'm thinking it might be the chain tensioners. Are they difficult to replace? Any other ideas? If I leave the car for a few hours it's doesn't do it at all. Overnight, does it a little bit the next day. A few days, quite loud (and sounds not great) but it is literally gone in under a second. Should I be concerned and dig deep into it more sooner than later? No issues seen in the filter. Engine runs super strong and smooth/quiet otherwise, just that first half a second on a cold start. Running Motul 8100 5W40 right now, plan on changing to Castrol Edge 0W40 next change.

A sound clip will help. Are you sure it's not the starter screeching (sticky gear)?

Oh no, definitely not a starter, it's internal engine and I'm 99.9% certain there is a direct correlation to oil pressure. I'll see if I can remember to do a clip next cold start.

I noticed that to some extent on my 99 as well. A cold start after a week or two of sitting sounds different from a cold start after a few hours of sitting. It just sounds harsh for a fraction of a second, and the rpm shoots to about 2K for half a second when it catches, then settles down to below 1K. Since it is only my infrequent weekend fun car, last time I started it after sitting for 10 days, I took the air filter box out, and hand turned the engine half a dozen turns with a 24mm socket before starting. It still went to 2k rpm for half a second, but the harsh sound was much reduced. The hand turning of the engine didn't build up any oil pressure, but I suspect it may prelube all the chains inside the engine. Kind of PIA to hand turn the engine, but I may continue to do that whenever I let it sit for a couple of weeks. I've pulled the fuel pump fuse in the past to get some oil pressure before actual starting, but it caused the ECU to set various pending faults even though it didn't trigger the check engine light. May be wire in a remote starter switch is the best solution for those of us who let the car sit for weeks without starting.

Mine does exactly the same. Oil pressure up to 5 until it gets warmer. Whatever it might be it's gone no worse in almost 6years of my ownership. I use the same oil as you do. RPMS settles at 800rpms after it gets warmer. I say that's normal for a 16yr old engine. It was doing it on cold start at 45000miles. It now has 81000miles. Unrelated the CEL came on recently showing a code of po446 and I have it booked into Porsche this morning for 10-30am.

That's interesting guys, it does lead me to believe it's "normal" but still concerned me when I first heard it. When I get home this afternoon I'll do my best to take a short video just to confirm it's the same as you guys are talking about. If so, I'd be curious if replacing the tensioners (could it be 1?) would help it...assuming that's the problem of course! Even if it is "normal" I'm not sure that they all do it. Mine has 113K KMS (70k miles)

My 99 does it too, every cold start. At first I was a little concerned, so I searched and read enough to determine it's considered a normal phenomenon, and nothing to worry about. Mine has 125k fun, fantastic miles on it.

I have never driven a Porsche that did not do this.

Can confirm, my 99 shoots to 2000 rpm for half a second then goes down.

O.P. 1, Check for camshaft deviation- Durametric 2. Use a lower viscosity oil (separate thread) if it is the HLAs leaking down/pumping up.

I spoke to the original owner to ask him about it. He said the car always did it since he bought it (he was the 2nd owner) and he and 2 other buddies both had 996's and he said they all did the exact same thing, and actually one was worse so I'm not going to worry about it. During a cold start after several days, it sounded like a skeleton masturbating in a filing cabinet filled with spoons for the half sec, but I'll let it be and just keep an eye on it if it gets worse/lasts longer. Well, maybe not quite that bad I am changing the oil viscosity next change so that could be interesting if it changes too.

Spud72: "Hey. My car's making a funny noise." Mechanic: "Oh yeah? Describe it." Spud72: "Well, it sounds exactly like a skeleton masturbating in a filing cabinet filled with spoons." Mechanic: "Ah, yes. I know that sound."

Could be some worn down VareoCam chain rails pads. Mine had the same noise and after disassembly I could see the wear.

My 01 does this also. I pull the fuel pump fuse C4 and spin her over 4-5 seconds. Cranks very quietly afterwards. I replaced the IMS and 1-3 bank tensioner. The 4-6 tensioner is 'upside down' compared to the others and so it leaks down. The new style tensioner supposedly addresses this issue. I bought one to swap it but was unsuccessful in reaching it even after moving the ac compressor over as far as possible. Anybody has success in swapping the 4-6 with engine in car? If so do it make a big difference?

The chain tensioner is similar in operation to a hydraulic lifter, they both have a pressure feed from the oil gallery and once charged with pressurised oil are supposed to stay pumped up by way of an internal one way valve , holding the pressure inside and keeping tension to take up the slack between the chain rail and the chain or valve stem and cam but over a period of time the oil leaks out , so when you first start up before pressure builds and re charges the lifter/tensioner there is noise as the parts chatter before they refill and tighten up , newer tensioners are supposed to be better, porsche upgraded these about four or five times, there are threads about this if you do a search !!

My '01 does it as well. I assumed it was paying homage to the early days. Kinda sounds like my old super beetle when it started up.

Most likely normal. Be careful you don't go over board with oil viscosity. If you are running 0w-40 now and switch to 5w-40 I doubt you'll notice any real difference in valve/chain clatter at cold engine start. Oh you might -- at first -- as the fresh oil helps quiet the engine. I notice this when I have the oil changed at 5K miles. The fresh oil makes a noticable reduction in engine start up noise. You can try a 5w-50 oil ( not a typo for 15w-50!) but of course its cold viscosity is still "5w" so you probably won't notice much difference once the oil has some miles on it. My Porsche techs recommend for Porsche engines that aren't used frequently, that sometimes sit for a few days or longer between uses, to run Swepco 502 Oil Improver. They state it helps quiet the engine clatter at cold start. I tried this stuff and didn't notice any change. However, I use my Porsches often and the engines don't sit but a day or two between uses. Don't run the oil too long. I've found engine noise increases as the oil mileage gets close to 5K miles. If you drive short trips 5K miles may be too many miles. Short trips load the oil with combustion byproducts like water and this lowers the viscosity of the oil and the engine becomes more noisy at startup.

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Hilarious, and accurate. Made me laugh out loud with that one!

If a guy wanted to do the tensioners and guides (and varocam guides) proactively, can that be done with the motor in the car? Pretty sure the tensioners themselves can, but I'm not clear of the guides can or not.

You can get two out of the three tensioners quite easy, the ims tensioner at the back underneath near the gearbox and the right hand bank tensioner, it's underneath on the head with the large hex nut on top, the left bank is harder as its on top of the head underneath all the stuff sat on top of the engine, id leave the vario stuff unless your getting fault codes stating cam deviation, don't know how much changing tensioners will solve your problem, I know there are newer type cam tensioners now , be careful with the ims one depending on your engine, it's got an external tensioning spring and is supposed to not fit early engines as the ims paddle is different inside , there are threads on this if you search

I had it and switched to DT40 oil. It's eliminated the noise except for a rare occasion when I might hear it for a second.

In most every case this is the IMS Tensioner. I'd start by putting the engine at TDC, and removing the tensioner... Clean it by purging it (pumping the piston up and down a lot while submerged) with Dexron/ Mercon ATF fluid until all of what comes out is clean. Then do the same thing with clean engine oil, and reinstall. The tensioners can become dirty and cause this. In most cases, replacing the tensioner is the only real fix for this, again, start with the IMS tensioner first. This can create were on the IMS tensioner paddle wear pad, and cause it to fail, so I always take this noise seriously, and address it.

Jake - no need to lock the cams before removing the IMS tensioner?

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No, as long as the engine is locked @ TDC, removing this tensioner is not a concern.

Thanks Jake I will do that and move it up in priority from "whenever I get a chance" to "soon". Would you recommend cleaning it as you suggest or just buy a new one for what they are worth? As a new Porsche guy I appreciate the assistance from you veterans E: I need to buy a crank pin lock tool. Is there a difference between 9595 and 9595/1? Stupid question but can I make my own or just use a bolt? Or would a kit like this be good enough for a casual wrencher? http://www.ebay.ca/itm/Porsche-Camsh...IAAOSw3mpXGWXc

Don't buy a crank pulley lock.. All you need is an 8mm or 5/16" bolt... Its the right diameter to pass through and pin. Here's the proper place to buy the tensioner, free shipping and expert support! http://store.rndeuroparts.com/catalo...Carrera/Engine

Thanks a lot Jake will do. Do I need anything else other than a seal (oring?) That I see as something to buy with it?

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Thats all you'll need..

You will need the crush washer I think , the rubber o ring will come with it.

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So I did the IMS tensioner this weekend along with all my maintenance to catch up on. Did a cold start today and I think it's still there... although a 24 hour cold stop it's always minor. Next stop the other 2 tensioners you think?

So, just revisiting this after a few months. I replaced all 3. Of course it was the last one, RH underneath the AC compressor quieted the racket down so it's no longer that same grating sound for the moment on cold start. There is still a sound when it's cold, but not like before. I'll know better after I let it sit for a week without a start, but I have definitely noticed a difference after almost 2 days of sitting. Also, I could tell on removal that one was relatively easily compressible by hand. When I primed the new one for install, it was absolutely rock solid.