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Black dots on dipstick

hey guys, i have a saab 9-3 with 180000 miles on it. recently when i went to check my oil, ive been noticing tiny black particles on my dipstick floating around. the particles are tiny like sand. and only 3-4 of them pop up once in a while
sometimes they also dissolve like an air bubble
Since then, i have got my oil and filter changed. I still see a few specks of it once in a while. I opened up my old filter to check it out. no large metal chunks but only specks dirt thats all.
what would those little particles on my dipstick be?

The only way to find out for sure is to take a sample to a lab for analysis.
My wild guess would be carbon, but it’s only a wild guess.

I agree. Time for an oil analysis for $25 or so.

Moisture condenses in the dipstick tube and rust develops over time, it is not unusual to see rust particles sticking to the dipstick on an older engine each time the dipstick is pulled from the tube.

I’ve never seen this before.

Try changing the oil and filter a few times in a row, driving 100 miles or so in between each change. If the problem goes away perhaps you got some contaminated oil or oil filter at some point. If it doesn’t go away, that could provide a clue too that whatever’s contaminating the oil must be coming from somewhere else other than the replacement oil and filter. The PCV system should be inspected for correct operation too. It is supposed to be sucking clean air into the crankcase as the engine runs. Perhaps something’s amiss with that. On my truck and Corolla that clean air comes from the air cleaner housing, but on some older vehicles there’s a separate little air filter that performs that job for the PCV system.

It will likely be less expensive to simply send an oil sample for analysis and know what’s wrong for sure…

just my 2 cents

If you have a Saab that’s lasted 180,000 miles, and there’s little dark spots on the dipstick?

Don’t worry about it!

And drive on!

Tester

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LOL, very well said!
But I have to admit that it would be nice to know what the spots actually are.

I’m not that anal when an engine has 180,000 miles on it.

Tester

A dirty dipstick tube on an old engine in nothing to worry about, changing the oil three times each after 100 miles is a waste of resources.

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