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Coolant / oil mix?


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Morning all,   Short history. 2004 C4S Cab.  I bought the car one year ago from a Porsche dealer.  One month later I smelled antifreeze inside the cab with the heat on.  
Another Porsche dealer garage pressurized the system for an hour showing no leaks.  The odor is still present.  I took it to a private Porsche specialist.  After three weeks,

pressurizing the system, changing the coolant, changing the oil and boro-scoping the cylinders, he found no leaks.  The odor is still present and getting stronger.  

I found yesterday my oil was one quart low.  I added a quart and found this.  See the photo.  I think I now have coolant mixing with oil.  I'm afraid to drive it but want other 

opinions before I start scheduling a mechanic to look at it or go back to the dealer where I bought it.   Thank you. 

996 Oil Cap.jpg

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Morning all,   Short history. 2004 C4S Cab.  I bought the car one year ago from a Porsche dealer.  One month later I smelled antifreeze inside the cab with the heat on.   Another Porsche dealer garage pressurized the system for an hour showing no leaks.  The odor is still present.  I took it to a private Porsche specialist.  After three weeks,

pressurizing the system, changing the coolant, changing the oil and boro-scoping the cylinders, he found no leaks.  The odor is still present and getting stronger.  

I found yesterday my oil was one quart low.  I added a quart and found this.  See the photo.  I think I now have coolant mixing with oil.  I'm afraid to drive it but want other 

opinions before I start scheduling a mechanic to look at it or go back to the dealer where I bought it.   Thank you. 

144679191_996OilCap.thumb.jpg.dcf79223f666858f0b830f3cd63b2c30.jpg

 

I had a coolant intermix on a 99 Cab that I purchased used last year. The oil under pressure was leaking from a cracked in the cylinder head into the coolant. The coolant had turned into a murky tan/brown sludge.

What I see on your fillet cap may just be condensation mixed with oil... hopefully.

 

It’s possible that you have a small leak in your heater core.

 

 

Sent from my iPad using Tapatalk

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Hate to say it but that yellow sludge in the oil filler tube and cap is a classic sign of not running the engine long enough and hot enough to burn that stuff off.  If you had the coolant system pressurized and leak tested, what makes you think you have a coolant leak? Surely something would have happened if the leak test failed.  And one quart low on oil?  When was the last oil change and how many miles on  the oil change?  It is not unusual to have to add a quart of oil every once in a while depending on mileage.  As said, if you are smelling coolant in the cabin (but again, you had a pressure test done on the coolant system so ????) it could be your heater core.  Are you losing any coolant?

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Hi Joe, thank you for getting back to me and for your time.  The car did sit for 2 weeks until I was able to change out my alternator.  I've driven the car quite a bit since.  The car sat running at idle 3 days ago while I was  charging a battery for my drone.  

 

I just looked at the coolant level.  It has not dropped at all.  You or someone else mentioned the heater core too.  That I may have a pin hole leak?  I have a new heater core in my garage but haven't replaced it yet.

 

The oil was changed at 72,683 or 2500 miles ago.   The car had 68,500 miles when I bought It.  It now has 75,300 miles.  I have never had to add any oil since I bought it.  The oil filler cap and the stronger smell of coolant is what got me worried.  

 

Again, thank you for hashing this out with me.  

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Aside from a cracked head (which you do not want), there are really only two other places where coolant and oil can mix.  One is the air oil separator (AOS) and the other is the heat exchanger on Bank 2.  It is generally that oil gets into the coolant since it is at a much higher pressure.  Have you checked your coolant tank for oil?  Use a turkey baster and remove some of the coolant and put it in a glass jar.  Oil and water will separate and you can see it. The old coolant was green and the new coolant is pink.  What does it look like in your coolant tank? Never a good idea to just let the car sit and idle.  Start and drive.  Plan a drive of 20-30 minutes at operating temperature (180+) and then check the oil filler cap.  You can also drop just your oil filter and put that oil in a glass jar and see if it separates.  In my opinion, it is not unusual to have to add a quart of oil after 2500 miles.

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And pull the panels on both sides of the battery.  Check the heater core hoses for any signs of a leak, because coolant could pool in the drainage areas under the panels and the smell could enter through the cabin filter intake.  Good time to check your drains under there as well.

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Thank you again, I have to travel 45 minutes tomorrow both ways so I'll wring it out and report when I return.  The new coolant is pink.  I opened the cap res cap this

morning and do not see any oil in it.  I will also try the turkey baster tomorrow and will also look under the panels next to the battery.

 

I didn't have a choice letting it sit.  My alt quit two weeks ago.  The Porsche dealer wanted $2350 to replace it.  I did it myself, but the alt, Pelican Parts sent was damaged. I had to send it back and order another alt.

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I occasionally noticed same gunk on my 911sc. With 996, think it’s especially important to always allow engine to reach op temp before pushing up the rpms. Also, unlike the older air cooled engines, the 996 is not, imho, meant for quick trips to the market. Once started I think it’s best to drive the car easy until thermostat opens up.  And then drive it with a little emphasis.  In heavy traffic, if engine properly warmed up, and fans working, temp should not raise dramatically.  Joe is right on the money. Good luck. Hope this is an easy fix. 

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Thank you Jon, I never run my RPMs above 2000 until the needle on the temp gauge comes alive.  Once it's warm it's not uncommon for me to shift at 3000.  I'll give you all an update after the weekend when I get a chance to look at the trays next to the battery compartment.   Thank you again for all of your help.

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Morning folks, I was able to drive the car a bit since my last post.  I inspected the area around the battery for any coolant leaks.  I found nothing.  I also 

inspected the coolant reservoir and it's maintaining it's proper level.  I also inspected the oil filler port but also smelled the port and only smell oil.  I don't

think I have a oil/coolant mix anymore.  I plan to replace the heat exchanger this week hopefully taking care of the awful coolant smell in the cabin.  Again

many thanks to you gents helping me sort this out.  

 

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