Oil In Coolant Reservior
Oil In Coolant Reservior Would anyone happen to know if the presence of engine oil soot on the coolant reservior stick is necessarily an indication of a leak from the gasket? Or rather, is there any other way oil could get into the coolant reservior besides a gasket leak?
Yes - Its probably not oil - its most likely power steering fluid. 
The fluid forms gooey clumps on the coolant resovior stick.
The SS and WS6 have power steering cooler, which is in-line with the cooling system. (Between the radiator and the engine.) I assume corrosion in the inside of the cooler allows the high pressure power steering fluid to enter the coolant system.
I had this happen to me when my car was new and the dealer fixed it under warranty. I got a new cooler and convinced them to power flush the system twice and that seemed to clear out all of the residue from the system. Been driving 60K since and had no other issues. (When it happened to me, both the dealer and I were stumpped. The dealer had to put in a call to GM engineers. - Its a very odd thing.)
If you want to post a picture of what your dipstick looks like, I can confirm if it matches what I saw with my problem.
The fluid forms gooey clumps on the coolant resovior stick.The SS and WS6 have power steering cooler, which is in-line with the cooling system. (Between the radiator and the engine.) I assume corrosion in the inside of the cooler allows the high pressure power steering fluid to enter the coolant system.
I had this happen to me when my car was new and the dealer fixed it under warranty. I got a new cooler and convinced them to power flush the system twice and that seemed to clear out all of the residue from the system. Been driving 60K since and had no other issues. (When it happened to me, both the dealer and I were stumpped. The dealer had to put in a call to GM engineers. - Its a very odd thing.)
If you want to post a picture of what your dipstick looks like, I can confirm if it matches what I saw with my problem.
Sometimes the dexcool will form a milk film like that. Mine started leaving a milky film in the overflow tank. i flushed it out really well and haven't had any probs with it since.
That's a good idea! I'll take a picture tomorrow and post it up.
The guy at Meineke told me that it was engine oil, judging from the orangy-yellow color. I had stopped by a Pontiac dealership today, and when asked, I was told that engine oil could get into the coolant reservior when there's an internal leak in the gasket. Up until I read all of your posts, I was convinced that it was engine oil, but now I have some hope that it's not as severe. Replacing a gasket at Pontiac's could cost $600 + labor, and over $2k for a head gasket. Yikes!
The guy at Meineke told me that it was engine oil, judging from the orangy-yellow color. I had stopped by a Pontiac dealership today, and when asked, I was told that engine oil could get into the coolant reservior when there's an internal leak in the gasket. Up until I read all of your posts, I was convinced that it was engine oil, but now I have some hope that it's not as severe. Replacing a gasket at Pontiac's could cost $600 + labor, and over $2k for a head gasket. Yikes!
Are you an A-4 or m6? The power steering cooler is external and does not tie into or through the engine cooling system so you can rule that one out. However if you are an a-4 the trans cooler in the radiator my be seeping. But the coolant would look like a strawberry milkshake and not yellow like you are describing. Yellow sure sounds like engine oil and the coolant are mixing at some point.
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Verdad Gallardo I did notice a brownish liquid on the dipstick, but it's the only separate substance from the yellow soot, so I assumed that's the coolant fluid. All I know about the coolant is that it's the 'green' type. The guy explained that GM engines get along fine with it.
Are you an A-4 or m6? The power steering cooler is external and does not tie into or through the engine cooling system so you can rule that one out. However if you are an a-4 the trans cooler in the radiator my be seeping. But the coolant would look like a strawberry milkshake and not yellow like you are describing. Yellow sure sounds like engine oil and the coolant are mixing at some point.
Once power steering fluid mixes with the stock coolant, its unrecognizable. It looks oily but has the consistency of ectoplasmic snot. The substance is so sticky that I couldn't get it off and also had to replace the coolant dipstick & cap.
BTW - Another tell tale sign of a power steering cooler problem is a very low power steering reservoir. When mine went, I lost power steering fluid at a very high rate.
I didn't get a chance to cut open the old cooler and see how it works/leaked, but I assume the power steering line coils around the coolant tube inside the cooling unit. The leak occurred at some location in the cooler where the two fluids flow next to each other. Since the power steering fluid is at such a greater pressure, I only had migration in to the coolant system and not vice-versa.
How is your power steering fluid level? (If its still normal, your problem is probably not a P/S cooler leak.)
I will get this taken care of at Meineke.
Thank you all for chiming in.
Getting in to head gasket issues can be expensive. If you are sure its not loosing PS fluid, then that makes a leaking cooler less likely.
If there's chocolate in your peanut butter, there's definitely peanut butter in your chocolate... If you aren't having any immediate performance problems, I'd suggest getting an oil analysis done. (I believe there are companies that will do it for $25 or so.) If you have a head problem and an oil to coolant exchange, they will be able to detect coolant/salts in your oil.
Not sure what a mechanic can do to confirm an oil to coolant leak or how much it would cost but an oil analysis should be an inexpensive way to put you on the right corrective path.
If there's chocolate in your peanut butter, there's definitely peanut butter in your chocolate... If you aren't having any immediate performance problems, I'd suggest getting an oil analysis done. (I believe there are companies that will do it for $25 or so.) If you have a head problem and an oil to coolant exchange, they will be able to detect coolant/salts in your oil.
Not sure what a mechanic can do to confirm an oil to coolant leak or how much it would cost but an oil analysis should be an inexpensive way to put you on the right corrective path.
Thank you very much for the suggestion. This is also what the guy at Meineke recommended--to just wait a while and see if the mixture changes in any way, which I presume is the fluid analysis you speak of. As for performance, it's great.
From what I understand, the oil could only be coming from either the intake manifold or the head gasket... or both. If the head gasket is blown, I was told that the temperature gauge would be at a noticeably higher level when driving on the highway. And yes, the cost of replacing either is considerable--$700-$1600. But if this is indeed the problem, I would like to have it taken care of right away to avoid any collateral damage to any of the other components.
As for the coolant mixing in with the enigne oil, it depends on where the leak is taking place. I don't remember the exact words, but I got the impression that the head gasket leak will allow direct contact of the fluids, whereas the intake manifold will usually allow only the oil to drip into the coolant.
It's scary to think that you could have an oil leak and not even know it. My oil stick showed a consistent full level, but some oil leaks are so gradual that you can't even see an indication from the stick until after a long time. This is in addition to not getting any drops on the ground, making you think that everything is A-OK.
From what I understand, the oil could only be coming from either the intake manifold or the head gasket... or both. If the head gasket is blown, I was told that the temperature gauge would be at a noticeably higher level when driving on the highway. And yes, the cost of replacing either is considerable--$700-$1600. But if this is indeed the problem, I would like to have it taken care of right away to avoid any collateral damage to any of the other components.
As for the coolant mixing in with the enigne oil, it depends on where the leak is taking place. I don't remember the exact words, but I got the impression that the head gasket leak will allow direct contact of the fluids, whereas the intake manifold will usually allow only the oil to drip into the coolant.
It's scary to think that you could have an oil leak and not even know it. My oil stick showed a consistent full level, but some oil leaks are so gradual that you can't even see an indication from the stick until after a long time. This is in addition to not getting any drops on the ground, making you think that everything is A-OK.
An interesting thing with our coolant system is the dipstick. The ladder-style stamping in the plastic will tend to gather substances. (Its engineered to use the coolant's surface tension to create "bubbles" across the rungs so you can see what the level is.)
So, I'd imagine that even a small amount of a foreign substance in the overflow tank would tend to gravitate to and stick to the dipstick.
So, I'd imagine that even a small amount of a foreign substance in the overflow tank would tend to gravitate to and stick to the dipstick.
Yes - Its probably not oil - its most likely power steering fluid. The fluid forms gooey clumps on the coolant resovior stick.
The SS and WS6 have power steering cooler, which is in-line with the cooling system. (Between the radiator and the engine.) I assume corrosion in the inside of the cooler allows the high pressure power steering fluid to enter the coolant system.
I had this happen to me when my car was new and the dealer fixed it under warranty. I got a new cooler and convinced them to power flush the system twice and that seemed to clear out all of the residue from the system. Been driving 60K since and had no other issues. (When it happened to me, both the dealer and I were stumpped. The dealer had to put in a call to GM engineers. - Its a very odd thing.)
If you want to post a picture of what your dipstick looks like, I can confirm if it matches what I saw with my problem.
The fluid forms gooey clumps on the coolant resovior stick.The SS and WS6 have power steering cooler, which is in-line with the cooling system. (Between the radiator and the engine.) I assume corrosion in the inside of the cooler allows the high pressure power steering fluid to enter the coolant system.
I had this happen to me when my car was new and the dealer fixed it under warranty. I got a new cooler and convinced them to power flush the system twice and that seemed to clear out all of the residue from the system. Been driving 60K since and had no other issues. (When it happened to me, both the dealer and I were stumpped. The dealer had to put in a call to GM engineers. - Its a very odd thing.)
If you want to post a picture of what your dipstick looks like, I can confirm if it matches what I saw with my problem.
Same thing here. fix the power steering cooler and flush your coolant and it will fix the problem
