Cold Start Engine Noise

[ivass]

I started noticing that when I first start the car in the morning the engine is a bit louder for about a second or two. It sounds like it needs some time to build enough oil pressure. If I turn the car off and start it again the noise is not there. Cars that I have had in the past used to have an oil valve (usually located around or within the oil filter) which did not allow oil to drain in the oil pan so the engine has instant lubrication when you first crank it. My guess is that my 99 C4 has the same valve, and that this valve is not functioning correctly. I was wondering if anyone can give me some more information on the subject.

Thanks in advance,

Ivo

99 C4

[djantlive]

Spin on type oil filter (those that are in a metal casing) typically offer an oil drain back valve if the filter is open downward. This prevents the oil from the filter to flow back into the engine block.

Porsche uses cartridge oil filter (only paper element). Our filters are do not open downward and are not spin on type.

As for your noise, I don't think you have much to worry about as long as the engine noise is not an exhaust rattle or leak, belt squeek. Check your oil level on a flat surface before starting once a week or two.

[Tool Pants]

Sounds like lifter noise which is 'normal' for a few seconds on a cold start. What weight oil are you using?

[ivass]

Spin on type oil filter (those that are in a metal casing) typically offer an oil drain back valve if the filter is open downward. This prevents the oil from the filter to flow back into the engine block.

Porsche uses cartridge oil filter (only paper element). Our filters are do not open downward and are not spin on type.

As for your noise, I don't think you have much to worry about as long as the engine noise is not an exhaust rattle or leak, belt squeek. Check your oil level on a flat surface before starting once a week or two.

I know that the 996 has cartridge oil filter and therefore no valve on the filter, but it must have a way of keeping the oil up in the engine.

Sounds like lifter noise which is 'normal' for a few seconds on a cold start. What weight oil are you using?

Yes, lifters... I use 0W-40 Mobil 1 and am located in Miami Florida, so most always is over 70F.

[1999Porsche911]

Spin on type oil filter (those that are in a metal casing) typically offer an oil drain back valve if the filter is open downward. This prevents the oil from the filter to flow back into the engine block.

Porsche uses cartridge oil filter (only paper element). Our filters are do not open downward and are not spin on type.

As for your noise, I don't think you have much to worry about as long as the engine noise is not an exhaust rattle or leak, belt squeek. Check your oil level on a flat surface before starting once a week or two.

I know that the 996 has cartridge oil filter and therefore no valve on the filter, but it must have a way of keeping the oil up in the engine.

Sounds like lifter noise which is 'normal' for a few seconds on a cold start. What weight oil are you using?

Yes, lifters... I use 0W-40 Mobil 1 and am located in Miami Florida, so most always is over 70F.

Stop using the 0W40. Move up to a 5W40 or 10W40 in the winter where you live. Only someone intent on destroying their 3.4 engine would run the 0W40. I won't even run that crap here in Chicago and it's currently 17 degrees outside. In the summer, you should move to a 15W50.

Porsche DOES NOT recommend 0W40 in your climate.

Edited December 10, 2005 by 1999Porsche911

[Kim]

Stop using the 0W40. Move up to a 5W40 or 10W40 in the winter where you live. Only someone intent on destroying their 3.4 engine would run the 0W40. I won't even run that crap here in Chicago and it's currently 17 degrees outside. In the summer, you should move to a 15W50.

Porsche DOES NOT recommend 0W40 in your climate.

You know, I really never understand it when someone puts up a post with a tone like this on a forum dedicated to the friendly sharing of information and insight. Maybe RennList .... but not here.

Of course, we all have differences of opinion on many, many subjects .... the right tire, exhaust system, ride height, etc .... but, on some subjects, concrete, authoritative information is fairly easy to come by. Porsche's latest TSB on approved oil recommends the Mobil Synthetic 0W40, as does my dealer (for my 3.4 engine) for any ambient temp .... which probably covers Miami year round. On the other hand, the TSB .... as far as I can find, does not recommend any 10W40 or 15W50 oils under any circumstances.

The bold print in the Engine Oil section of my Owners' Manual says, "if in doubt, consult your authorized dealer", so I guess its OK to trust him on this. However, I find no fault with, and have no argument with anyone who chooses to go another way. Porsche approves many different oils, both manufacturers and weights.

Finally, I guess I must misunderstand what the TSB says regarding viscosity: You recommend chucking the 0W40 in favor of the 5W40 or 10W40 for the Miami winter ... presumably because those south Florida winters are warm. But, all three of these oils will have the same viscosity at higher temps; the only difference coming into play at an ambient temp below -12F. At that point, the 5W40 would have to be swapped out for 0W40 if a new ice age came to Florida .... and the 10W40 could only be used if one chose to ignore Porsche's latest info.

As always, I stand ready to be educated and corrected in my never fully adequate understanding of these wonderful machines and their mysteries. You guys will surely let me know if I've failed Properties of Oil 101.

Kim

2000 Cab

[1999Porsche911]

Stop using the 0W40. Move up to a 5W40 or 10W40 in the winter where you live. Only someone intent on destroying their 3.4 engine would run the 0W40. I won't even run that crap here in Chicago and it's currently 17 degrees outside. In the summer, you should move to a 15W50.

Porsche DOES NOT recommend 0W40 in your climate.

You know, I really never understand it when someone puts up a post with a tone like this on a forum dedicated to the friendly sharing of information and insight. Maybe RennList .... but not here.

Of course, we all have differences of opinion on many, many subjects .... the right tire, exhaust system, ride height, etc .... but, on some subjects, concrete, authoritative information is fairly easy to come by. Porsche's latest TSB on approved oil recommends the Mobil Synthetic 0W40, as does my dealer (for my 3.4 engine) for any ambient temp .... which probably covers Miami year round. On the other hand, the TSB .... as far as I can find, does not recommend any 10W40 or 15W50 oils under any circumstances.

The bold print in the Engine Oil section of my Owners' Manual says, "if in doubt, consult your authorized dealer", so I guess its OK to trust him on this. However, I find no fault with, and have no argument with anyone who chooses to go another way. Porsche approves many different oils, both manufacturers and weights.

Finally, I guess I must misunderstand what the TSB says regarding viscosity: You recommend chucking the 0W40 in favor of the 5W40 or 10W40 for the Miami winter ... presumably because those south Florida winters are warm. But, all three of these oils will have the same viscosity at higher temps; the only difference coming into play at an ambient temp below -12F. At that point, the 5W40 would have to be swapped out for 0W40 if a new ice age came to Florida .... and the 10W40 could only be used if one chose to ignore Porsche's latest info.

As always, I stand ready to be educated and corrected in my never fully adequate understanding of these wonderful machines and their mysteries. You guys will surely let me know if I've failed Properties of Oil 101.

Kim

2000 Cab

I didn't know I was so harsh wth my reply, but after readings it again, I see where someone might take it that way. Oh well.

As fas as Porsche TSB's on approved oils, it is not a recommnedation to use 0W40. That is only an aprroved oil. We all know (or should know) that a 0W40 oil will not protect an engine that normally runs an oil temp in excess of 230F. Furthermore, people have come to believe that becasue 0W40 is the factory fill, that is a recommendation from Porsche to use it in all climates. It is not. In past TSB's Porsche specifically outlines what weight oil to use in all climates, and in Florida's climate, the suggested weight IS NOT 0W40.

The chart below has existed for 30 years. What changed? Maybe just wanting to get a litlte better short term performance out of the engine or a little better gas mileage? The oil didn't change. It still is not certified for any temp above 212F. Our engines run considerably hotter than that.

Edited December 10, 2005 by 1999Porsche911

[Hroussard]

Folks, I am looking at a bottle of Mobil 1 0W-40. It states " Mobil 1 0W-40 provides the high temperature protection of a 40 weight oil combined with the easy cold starts of a 0 rating.

Protects at oil temperatures at 400 degrees Fahrenheit.. excellent cleanliness and wear protection in high temperature / hot-running engines, even at longer drain intervals.

Sounds to me that California and Florida is covered in this statement.

Regards

[1999Porsche911]

Folks, I am looking at a bottle of Mobil 1 0W-40. It states " Mobil 1 0W-40 provides the high temperature protection of a 40 weight oil combined with the easy cold starts of a 0 rating.

Protects at oil temperatures at 400 degrees Fahrenheit.. excellent cleanliness and wear protection in high temperature / hot-running engines, even at longer drain intervals.

Sounds to me that California and Florida is covered in this statement.

Regards

What is the protection? Do a little research and you'll see its not for shear strength which is what you need in a high reving, high temperature engine. But, I have no stake in what people use, but have rebuild a few dozen engines that used low viscosity oils. They are not pretty. If it doesn't cause all your seals to leak so you have to replce the engine, you have a good chance seeing the downside of the 0W40 when you get some high miles on the car. Valve guides in particular, along with main bearings. But, to each their own.

[Hroussard]

1999Porsche911, I buy your argument. It does amaze me though that the local Porsche dealerships here in California religiously want to fill / refil with 0W-40.

Based on your input it seems that one would want to change oil at least twice a year , ie winter versus summer. From your experience what would a oil drain / refill schedule look like?. I live in Northern California where it never freezes but where, in the Summer, temps will go up to 100 degrees.

Appreciate you sharing your knowledge and experience.

HarryR1999C2

[Kim]

The chart below has existed for 30 years. What changed? Maybe just wanting to get a litlte better short term performance out of the engine or a little better gas mileage? The oil didn't change. It still is not certified for any temp above 212F. Our engines run considerably hotter than that.

I must be missing something in the chart. It appears that 0W-40 shares the bar with 5W-40, and they both indicate exceeding (I assume that's what the arrow at the top means) the same temp range as the other oils pointing out the top. If there is a point on that chart that shows some oils protecting all the way to 230, while 0W-40 tops out at 212, then I'm missing it.

With the chart being 30 years old, does it take modern synthetic oils into account? I have no idea if that makes a difference, but my owners' manual clearly differentiates in specifying viscosity ranges for synthetic and non-synthetic oils.

Again, I challenge no one's choice of oil. I just don't understand your stance, nor your parsing a difference between Porsche "recommending" an oil, and Porsche specifying, by brand and weight, which oils it approves for specific ambient temperature ranges.

I have no intention to be argumentative, but I enjoy an exercise in logic .... even if that excercise eventually proves me in the wrong. I just haven't seen that, yet.

Kim

2000 Cab

[brewcity996]

Hey guys I don't chime in much (but I do drop in EVERYDAY for a read) and I think you may have got off track on this one. The poor guy is worried about a rattle when he starts his beloved P-Car in the morning. So I just want to say ALL 3 of my 9X6 cars have done this, none have ever leaked anything, died, fell apart, or ever left me hanging in the very extreme temps. in Milwaukee (0ish,now to 90ish summer). More importantly, I think (know), I read a post here about this being some kind of air punp or emissions pump making the noise when the car is started cold.

[umn]

Sounds like lifter noise which is 'normal' for a few seconds on a cold start.

Exactly. It's likely to be just the hydraulic tappets, nothing to worry about.

Basically when you stop the engine, some of the valves are in an "open" position. The resulting force presses the oil out of the hydraulic tappets and it takes a few seconds for them to refill when the engine gets started again.

Cheers

Uwe

[ivass]

Sounds like lifter noise which is 'normal' for a few seconds on a cold start.

Exactly. It's likely to be just the hydraulic tappets, nothing to worry about.

Basically when you stop the engine, some of the valves are in an "open" position. The resulting force presses the oil out of the hydraulic tappets and it takes a few seconds for them to refill when the engine gets started again.

Cheers

Uwe

Thanks

[Gabo2k]

Folks, I am looking at a bottle of Mobil 1 0W-40. It states " Mobil 1 0W-40 provides the high temperature protection of a 40 weight oil combined with the easy cold starts of a 0 rating.

Protects at oil temperatures at 400 degrees Fahrenheit.. excellent cleanliness and wear protection in high temperature / hot-running engines, even at longer drain intervals.

Sounds to me that California and Florida is covered in this statement.

Regards

What is the protection? Do a little research and you'll see its not for shear strength which is what you need in a high reving, high temperature engine. But, I have no stake in what people use, but have rebuild a few dozen engines that used low viscosity oils. They are not pretty. If it doesn't cause all your seals to leak so you have to replce the engine, you have a good chance seeing the downside of the 0W40 when you get some high miles on the car. Valve guides in particular, along with main bearings. But, to each their own.

1999porsche911:

I live in Southern California. Temperatures range from 65 to 110 year-round. What oil would you recommend I use? I currently run on factory-fill 0-40W Mobil 1

Thanks.

[1999Porsche911]

1999porsche911:

I live in Southern California. Temperatures range from 65 to 110 year-round. What oil would you recommend I use? I currently run on factory-fill 0-40W Mobil 1

Thanks.

Personally, I would run 15W50 all year round. There is no need to go with an oil that is "pourabe" at -60F. You will be fine, also, running 5W50 but the oil has more additives in it to maintain the higher 50W rating. This really is not a problem if you change your oil at regular 5,000 miles or less intrevals. Castrol Syntac makes both weight oils. Are you going through as much oil in the hotter months as you do gas using the 0W40?

Edited December 14, 2005 by 1999Porsche911

[nycebo]

I just added Mobil 15W50 to my car. I live in New York. I have no idea what I am doing and am going to rummage the net for some better clarification.

[nycebo]

Okay, I found this information on the Mobil web site using their 'Help me decide' tool for selecting the appropriate oil for the car (I guess Kim was right):

What's the right oil for my car?

The company that manufactures your vehicle recommends this Mobil 1® product, or has a special requirement.

Current Vehicle:

Year: 2000

Make: Porsche

Model: 911

Engine Type: 6cyl. 3.4Liter

Mobil 1 0W-40

A fully synthetic motor oil, Mobil 1 0W-40 with SuperSyn Technology exceeds industry standards and the major leading builder requirements, enabling the product to keep performing well after conventional oils cannot. Mobil 1 is recommended by leading car manufacturers as initial fill.

Special Filter Not Required

This website contains the most current information available at the time of website launching, and is updated periodically. Always consult your vehicle manufacturer's manual for information specific to your automobile.

I guess the next question should be if there is any advantage or disadvantage using the 15W50 if Porsche is specifically stating that we use 0W40. I'll check around and get back to you.

[1999Porsche911]

I just added Mobil 15W50 to my car. I live in New York. I have no idea what I am doing and am going to rummage the net for some better clarification.

Edited December 21, 2005 by 1999Porsche911

[nycebo]

Okay, I went to PCA (Joel Reiser is one of the more knowledgeable and informative guys out there) to find more detail on oil (https://www.pca.org/tech/tech_qa_question.asp?id={D511B82E-9AE1-4564-8F74-724C0847AD24}). Here's what he had to say:

"The 15W-50 is for warmer climates and/or tougher service, and the 0-40 is for cooler climates. I hope I did not misunderstand the question. 0 will flow better at a lower temperature than 15 will. Likewise the 50 will handle the higher temps better than the 40 will. In warmer weather and on the track I run the 15-50, whereas I run 0-40 in my street car for the cold winter weather. So I would say 'no, it only has advantages for the colder weather'.

Since publishing the note above, I have additional information from Bruce Anderson and Peter Smith to pass along. Porsche is currently recommending the following in Technical Bulletin 1701, "Engine Oils Approved by Porsche":

Castrol/Syntec 5W-50

Exxon/Superflo Supreme Special 15W-40

Mobil 1 5W-30, 10W-30, and 15W-50

Sunco Synturo Gold 5W-40

Havoline Formula 3 synthetic 5W-40

Valvoline/ High Performance Synthetic 5W-30

Note that Mobil1 0W-40 was not available yet at that point in time.

We are thinking that Porsche favors the 40 top weight over the 50 for street use because it is friendlier to the hydraulic valve adjusters (993 and 986/996) and other areas of the VarioCam valve train (986/996). In the case of the former, we have seen some of these newer cars struggle to achieve compression on startup in certain circumstances because the hydraulic valve adjusters are not pressurizing correctly.

So the revised answer is 'yes, it offers valvetrain advantages provided you keep the oil temperatures within specs'. In other words I will still run 15W-50 in my GT3 Cup car with the hydraulic valve adjusters because it is still heavier duty service than a 0-40 would be best for. But on the newer street cars the 0-40 is probably better if your climate is not hellaciously hot and you don't overdrive the car.

Joel Reiser / Bruce Anderson- PCA Website 2/02"

He also wrote (https://www.pca.org/tech/tech_qa_question.asp?id={512C8E59-91E5-4222-A730-89791DA56B43}):

"Just a little over a month ago on 11-30-01, Porsche issued a new oil bulletin that is significantly changed. The latest list of approved synthetic motor oils from Porsche includes Mobil 1 0W-40, Mobil 1 5W-40, Valvoline High Performance Synthetic, 5W-30, and there is also a Castrol/Syntec 5W-50 listed. As before, Porsche says the oils can be used for all 4, 6, and 8 cylinder Porsche engines from 1973 on. The Mobil 1 0W-40 now comes in all the new Porsches, including the Turbos, but some owners have had a problem finding it in retail outlets. The biggest change in this latest data is that temperature charts lowered the upper limit on the 0W-30 synthetic oils that were previously 40C (104F) to 30C (86F). These newest Porsche temperature charts do not show a synthetic 10W-30, but do show 10W-40s and 5W-40s going to a higher (but undefined) temperature limit than the 0W-30 synthetic oils which have the revised lower maximum limit of 86F ambient temperature. We will keep trying to learn more about these changes and pass them on, but in the meantime, I guess I would feel better about a 5W-40 or higher oil for running under warm ambient temperatures."

So, I don't know whether the smart thing is to go with 0W-40 or 5W-40 from here on. Since I am in the northeast, I'll likely stick with 0W-40. 1999Porsche911, I get what you are saying, and always prefer to err on the side of caution, but do you think that the 15W-50 is really that much better or more warranted?

Cheers.

[Loren]

Porsche publishes a new "Approved Oil" bulletin every year. Contributing Members here can view the current bulletin online here.

Joel and Bruce are tremendous resources to the Porsche community but sometimes their information is not current. Mobil 1 5W-50 has been off the "Approved Oils" list for over two years.

[nycebo]

Porsche publishes a new "Approved Oil" bulletin every year. Contributing Members here can view the current bulletin online here.

Joel and Bruce are tremendous resources to the Porsche community but sometimes their information is not current. Mobil 1 5W-50 has been off the "Approved Oils" list for over two years.

Loren, if you look at the date of their post, you'll notice that it's from Feb 2002. I just posted it because my car is a 2000 and it was one of the more pertinent of their responses. I am optimistic that they have the newer bulletin.

[1999Porsche911]

Okay, I went to PCA (Joel Reiser is one of the more knowledgeable and informative guys out there) to find more detail on oil (https://www.pca.org/tech/tech_qa_question.asp?id={D511B82E-9AE1-4564-8F74-724C0847AD24}). Here's what he had to say:

"The 15W-50 is for warmer climates and/or tougher service, and the 0-40 is for cooler climates. I hope I did not misunderstand the question. 0 will flow better at a lower temperature than 15 will. Likewise the 50 will handle the higher temps better than the 40 will. In warmer weather and on the track I run the 15-50, whereas I run 0-40 in my street car for the cold winter weather. So I would say 'no, it only has advantages for the colder weather'.

Since publishing the note above, I have additional information from Bruce Anderson and Peter Smith to pass along. Porsche is currently recommending the following in Technical Bulletin 1701, "Engine Oils Approved by Porsche":

Castrol/Syntec 5W-50

Exxon/Superflo Supreme Special 15W-40

Mobil 1 5W-30, 10W-30, and 15W-50

Sunco Synturo Gold 5W-40

Havoline Formula 3 synthetic 5W-40

Valvoline/ High Performance Synthetic 5W-30

Note that Mobil1 0W-40 was not available yet at that point in time.

We are thinking that Porsche favors the 40 top weight over the 50 for street use because it is friendlier to the hydraulic valve adjusters (993 and 986/996) and other areas of the VarioCam valve train (986/996). In the case of the former, we have seen some of these newer cars struggle to achieve compression on startup in certain circumstances because the hydraulic valve adjusters are not pressurizing correctly.

So the revised answer is 'yes, it offers valvetrain advantages provided you keep the oil temperatures within specs'. In other words I will still run 15W-50 in my GT3 Cup car with the hydraulic valve adjusters because it is still heavier duty service than a 0-40 would be best for. But on the newer street cars the 0-40 is probably better if your climate is not hellaciously hot and you don't overdrive the car.

Joel Reiser / Bruce Anderson- PCA Website 2/02"

He also wrote (https://www.pca.org/tech/tech_qa_question.asp?id={512C8E59-91E5-4222-A730-89791DA56B43}):

"Just a little over a month ago on 11-30-01, Porsche issued a new oil bulletin that is significantly changed. The latest list of approved synthetic motor oils from Porsche includes Mobil 1 0W-40, Mobil 1 5W-40, Valvoline High Performance Synthetic, 5W-30, and there is also a Castrol/Syntec 5W-50 listed. As before, Porsche says the oils can be used for all 4, 6, and 8 cylinder Porsche engines from 1973 on. The Mobil 1 0W-40 now comes in all the new Porsches, including the Turbos, but some owners have had a problem finding it in retail outlets. The biggest change in this latest data is that temperature charts lowered the upper limit on the 0W-30 synthetic oils that were previously 40C (104F) to 30C (86F). These newest Porsche temperature charts do not show a synthetic 10W-30, but do show 10W-40s and 5W-40s going to a higher (but undefined) temperature limit than the 0W-30 synthetic oils which have the revised lower maximum limit of 86F ambient temperature. We will keep trying to learn more about these changes and pass them on, but in the meantime, I guess I would feel better about a 5W-40 or higher oil for running under warm ambient temperatures."

So, I don't know whether the smart thing is to go with 0W-40 or 5W-40 from here on. Since I am in the northeast, I'll likely stick with 0W-40. 1999Porsche911, I get what you are saying, and always prefer to err on the side of caution, but do you think that the 15W-50 is really that much better or more warranted?

Cheers.

I wouldn't run the 15W50 this time of year in the NE. However, the 50W in the summer will provide you with significantly more protection on the 3.4 engine because the engine runs extremely hot. 15W50 is what I use, but would not shy away from using 5W50 either. It is the 50 that will protect you more from shearing the oil at high temps.

Porsche has no idea what they are doing with their oil recommnedations. As a matter of fact, they do not make any recommendations anymore, but simply give you a list of "approved oils". Many, many dealers will fill your crankcase with 15W50. The fact is, a 15W50 oil flows the same as a 0W40 oil all the way down to 14 degrees and a 5W50 flows the same all the way down to -20F.

Edited December 21, 2005 by 1999Porsche911

[Kim]

Joel and Bruce are tremendous resources to the Porsche community but sometimes their information is not current. Mobil 1 5W-50 has been off the "Approved Oils" list for over two years.

I have noticed the same thing regarding Joel's PCA.org Q&A. He has access to a wide array of experts and information and often comes up with terrific answers .... but a regular reader will occasionally see an answer that indicates his being a little behind in some area that has already become widespread knowledge among many Porsche drivers .... particularly those who frequent here.

The bottom line, I guess, is that no one source is going to have all the answers.

Kim

2000 Cab

[nycebo]

The fact is, a 15W50 oil flows the same as a 0W40 oil all the way down to 14 degrees and a 5W50 flows the same all the way down to -20F.

It's hard to argue with that logic, and the 50 will save the trouble of having to worry about temps in the summer when it breaks into the 90s here.