Noise on cold engine start (not valvelifters I guess)

Hi, I recently get a ticking noise about 30 seconds after a cold start of the engine which resembles the knocking noise of an old diesel engine although not as loud. Most of time it's tick-tick-tick with about o.2s pause in between the ticks and then again after 5s or so tick-tick-tick again . After that everything is normal.I'll try to link a (bad quality) sound file I've recorded. The file gives a wrong impression about the volume of the ticks though. It's not as loud as it seems.The whole thing lasts about 30s. The car is a 99 C4 with 78300km on the clock. I already had my 80000km inspection done 2 weeks ago with oil change from Mobil1 0W-40 to 5W-50 done by myself last week. I only noticed the noise after I had already done the oil change. Should have noticed the sound if it would have been there earlier because I usually drive the car out the garage and then walk around it to load my luggage on the rear seats setting off to work. If have no idea though why the oil change or the inspection should be a cause.(Oil level is fine) Any thoughts? Thorsten Click to download soundfile

Toddel, I first noticed ticks, similar to yours when my oil was changed from 40 to 50 wgt (indy insisted 50 was best for TX heat). My guess is that is your root cause too. I am sure an oil debate will commence. I am tempted to go back to 40wgt especially with the falling temps. IMHO of course, RB

I have a '99 C4 and went to 5w-50 for the summer as a result of the oil debates on this forum. I noticed noise when I started the car in the morning as well. I recently switched back to 0w-40 for the winter and the startup ticking went away. I thought it was all my imagination, but maybe not. edit: I just listened to the sound file. That does sound harsh, even keeping in mind that you said the ticking was magnified. I think mine went away after 5-10 seconds.

Have you attempted to locate where the noise is coming from by looking at the engine when it is making noise? Did YOU change the oil. What weight? What is your oil pressure at idle, cold? After driving the car to full temperature and shutting it down, will it make the same noise if you start it in 3 - 4 hours? Sounds awful harsh for a valve unless one is either bone dry or broken.

I did the oil change myself, so it's definitely Mobil 5W-50. Oil pressure is almost full up on the scale when cold and drops to mid range when hot. Noticed no change there. Outside temp has been around 8 C (46 F) during the last days. So far I could not hear any noise when the car was parked for a period like 3-4 hours but I've done that only two times since then. Hard to imagine that a change from 0W to 5W makes the difference. Thorsten

Had to edit my last post because I had written 15W-50 by mistake. The source o the noise seems to be the top area of the motor but that's really hard to tell.

Even running a 15W50 would not cause that kind of noise. I still have it in one of my 996's and I get no noise at all even after sitting for 1 week in 30F temperatures. However, a freind who runs 0W40 in his 997 gets it all the time at startup, but considerably quieter and with less duration than your sample sound file. IF it is a valve, the only thing that would cause that kind of noise is dirt blocking the flow. See if you can maybe get a general feeling for the area of the engine the noise is coming from. Sometimes electical arching can sound similar to a mechanical noise. Look at the engine when the noise is present in total darkness.

The sound file is a little bit overdone on the relation of ticking noise to the noise of the engine itself. I guess it's the microhone characteristics of my PDA which I used for recording. Funny thing is that I tend to say that the usual valve lifter noise which I referred to in my topic title is much less now. Thorsten

Also check the easy things, such as eliminating the secondary air pump by unplugging it before starting the engine, tools that may have fallen into the engine compartment and the electric resonance valve is not hitting against the alternator,

Damn, that ones got me stumped. At first, it sounded like a shredded accessory belt slapping somewhere but the fact the sounds goes away rules that out. Since the sound goes away, I assume it has to do wth expansion from heat closing a "gap". Weird ticks I have heard on cars: 1. loose spark plug (compression leaks past plug) 2. smog pump one way check valve (sounded just like a spun rod bearing, not making this one up) 3. of couse a loose rocker arm 4. worn out idler pulley 5. broke off valve stuck to my piston (too much boost, hard lean) 6. leaking header gasket 7. blown out head gasket (again too much boost, hard lean) It is amazing how leaking compression or combustion can sound like a ticking or knock but I highly doubt any of these things would have occured on your car, just throwing out some ideas to stimulate someones brain for the cause.

Toddel, I just listened to your sound byte. Your ticking does seem similar to what my car does only maybe a little louder. Hard to tell on the recording. But for me, it goes away completely in less than 10 seconds and does not cycle like yours. Could be your clearances are just more sensitive to the new oil. Just in case, I would let her warm up well before any higher revvs. Good luck on a remedy. RB

is your car a tiptronic?

Use 0w40 or 5w40...These cars do not need or want a 50wt. oil....There are very sprecific reasons for that...Do a search and you will see the topic disccused in the 996 and 997 forums extensively.

At start up, there is no difference between a 5W50and a 5W40, so your theory does not hold water, or oil for that matter.

Popcorn time! Come and get it!

Not again...After all the data and facts you just can't get it! There is a cold flow property difference. It is a fact.Accept it. Deal with it. And quit giving innocent Rennlisters bad advice. I can't believe I took the bait again....

Your noise sounds like it's at engine speed, not half-speed that would indicate a valve train source. Bill

Brant - you want a drink with that popcorn? It's "on the house!"

So, you are saying that a 5W40 oil does not have the same flow rate as a 5W50 at start up? I just want to make sure that you are stating this as fact and not emotion. Are you also saying that using 5W50 is not good for the engine? Again, just trying to get the facts here. Answering yes to either of those questions, would, do I dare say it, make YOU wrong. 5W50 IS approved by Porsche so it must be ok to run in your engine, right? I mean, you always state that is Porsche approves something, then it is the only way to go. Kinda like having to run "N" rated tires, right? Oh yeah, you don't follow THAT recommendation. I wonder why? There is a difference in arguing about something that is opinion based or a result of particular expereinces and simply stating incorrect information, as you have here.

Pass the drink please!!

Only in my worst nightmares

Do I get you right? You say it's NOT a valve train source?

I want my thread back! Can't we just agree on that there's no difference between 5W-50 and 5W-40 on cold start and only a slight difference between 0W-40 and 5W-50 (according to specs) which shoudn't be noticable by the average Porsche guy? I think you guys were comparing two different pairs of viscosities. Thorsten

Thorsten. By chance, do you park your car normally in a position that keeps the back of the car higher than the front? i.i. backing into your garage.

Lifter noise...several taking longer to pump up with heavier oil when cold. Happens all the time with many different types of vehicles. Why do you think they came out with 0w oils in the first place?

yet the trend tends to be MORE lifter noise with 0w40 than heavier oils.

I park the car levelled though the driveway of 5m length has an angle of > 22�. So driving in that means backing up downhill with a clearance of 2cm at the exhaust tips. Driving in forward is impossible since the nose would hit the gound Nevertheless I've also noticed the noise after parking at work. Thorsten

it sounds like a bad lifter to me, colapsed or contaminated

"yet the trend tends to be MORE lifter noise with 0w40 than heavier oils." May bleed down quicker after sitting resulting in initial noise, but noise will quickly diminish because oil supply will quickly refill the collapsed lifter. Oil debates are like fighting with double edged swords, LOL

That is a noisy lifter. Cars that have the lifters up with the cams it becomes a physics issue. They will be empty and dry if the has been sitting. My car does that when it is cold and sitting for a few days. My FX45 and A6 did it as well. What I do not like is the sound is not going away. On my A6 there was a known issue that Audi put a screen filter before the lifters. Over time it becomes clogged. You may want to conceder an engine flush. On the other hand I would use the 0w oil. It will help get the oil up to the valve train. Jut my 2 cents..

FLUSH ISNT GOING TO HELP HES LIKELY GOING TO NEED TO REPLACE IT

Not to debate, Just wondering why I got lifter noise and/or knock on startup, immediately after the oil was changed and with only about 1yr and 2k miles on the old oil. If 5w - 40/50 have no flow diff, can I assume my old oil may have been 0w/40 (put in in Bellevue, WA) vs the new change that I know was 5w/50 in Dallas. Just wondering which oil should I go back to 0w or 5w, if the knock gets worse. As of now, I consider it near normal for cooler temps and it goes away rapidly. RB

No matter what oil you have in your car, the longer the car sits without running the engine, the more oil that will leak out of the lifters that are on the cam lobe. Thinner oil will leak out more quickly than will a thicker oil. In these cases, it is normal and should be expected to hear this lifters make noise until they fill with oil. Many cars also have problems with start up knocking if the frontend of the engine is much higher than the front while parked due to oil flowing away from engine parts. In the case of the flat six, there is better oil maintained on important engine componants if the back of the car is not higher than the front when parked for long periods of time.

People please read this http://63.240.161.99/motoroil/ I think you'll get a better understanding of oils and weights before you make assumptions that you're an oil expert. There is differences in more then just the numbers.

What makes AE Haas the expert?

He has his own web page. I gotta get me one of those. Then people will follow me evrywhere.

So can we finish our popcorn and drinks and go back to Thorsten's thread... Let's say that it turns out his car may have a valve lifter problem, and his car is still under warranty. What can he expect from Porsche? 1) A replacement of the valve lifter banks or 2) New engine? Anyone? Cheers.

mine is, and i have this same noise. any more info?

Thank you for trying to steer the thread back. Unfortunately the car is not under warranty any more... Just to clarify: the recording covers all the noise there is - it's the stretch from 30 to 60s after startup and before and after there is no such noise. Thorsten

You can try a flush or some addtive i like lucas oil additive, but chances are eventually you will need a set of lifters

Maybe the fact that he has actually study hydrodynamics? I'm not saying its pure gold facts, but it hold more weight then any other comments made. As far as getting back to the subject at hand, I say the best thing to do is to try switching back to the 0W-40 to see if it gets rid of the noise. It can't hurt any contrary to some people beliefs. It it continues to have noise you have two choices live with it or have the valvetrain taken apart.

If your lifters quiet down shortly after start up, you don't have a problem as far as they are concerned. Noisy lifters usually surface when the oil is hot and RPM is low, I know the oil is thicker when hot, (???) but oil pressure is lower at low rpms. Also if you change to a lighter 0W oil the noise may not immediately be any different as the lifters will still have the oid oil in them and you will have to go thru several drive and park cycles to get them all to bleed down and get refilled with the new lighter oil.

Sorry it took me quite a while to give some feedback but I wanted to make sure that my engine is in a stable state now. For several weeks now I haven't heard anything from the engine and even after a final 'test' with the car resting for two weeks at temps around freezing point there was no ticking. So the conclusion seems to be that the engine needed some break in time with the 5w-50 oil. (I wish I could offer a mor logical explanation). Overal I'd say the engine is running much smoother now when idling warm. But that might just be an illusion and certainly not enough reason to start the great oil debate. Thorsten

I wonder how many engine issues are due to the fact that not all P-cars are driven daily...

I bet lots, no disrespect intended to the low mileage guys. It's true of any car, really. But you have to consider what these were built to take, and then imagine them languishing in garages or sitting in urban North American traffic. I haven't counted, but it seems to me like a lot of the bad engine stories include the phrase "... only has X miles on it!". I don't judge the people who don't drive them daily. Mine doesn't get the use it should. I just think that you have to accept that, to an engine, low mileage, low speed driving and prolonged storage are abuse, and plan and budget accordingly. That's how I deal with it, anyway.

I've just read for years how some guys have 911s with over 200k miles on them and drive them loads of miles daily... Other than a certain type of material (ie: rubber seal or gasket) contracting and swelling due to non-use, I can't logically find reason for a low mileage car to have issues... surely cars can't get "into grooves" and perform better by being driven all the time, but maybe they can...

I wonder how many engine issues are due to the fact that many use the wrong oil?

Over my head. But when I was a Bimmer guy, every mechanic I ever talked to in fifteen years of ownership said the cars that were driven the hardest were the ones that had the fewest problems other than wear items. I came to believe that there must be some physical explanation, but I couldn't tell you what. Wait, unless it was oil. I think if you drive hard on odd numbered days and use 50W1,000,000, it's better. Or something like that.

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Sorry it took me quite a while to give some feedback but I wanted to make sure that my engine is in a stable state now. For several weeks now I haven't heard anything from the engine and even after a final 'test' with the car resting for two weeks at temps around freezing point there was no ticking. So the conclusion seems to be that the engine needed some break in time with the 5w-50 oil. (I wish I could offer a mor logical explanation). Overall I'd say the engine is running much smoother now when idling warm. But that might just be an illusion and certainly not enough reason to start the great oil debate all over again. Thorsten