Possible blown head gasket?

hey guys, ive been very paranoid about my head gasket. I dont have any symptoms of a blown head gasket, e.g white smoke, overheating, milky oil, losing coolant etc.
Is it possible that a head gasket can blow without showing any symptoms at all? or do these symptoms always show up?


The latter.


What’s your make/model/year? Is this just a general info question, or do you have some unexplained symptoms which you think might be the head-gasket lazing on the job?

its a 2006 saab 9-3 arc.
theres a short hiss when i open the coolant expansion tank after its been running. and just some whitish smoke when i rev the car when its cold in the morning. but not when its warmed up. and not after if its been driven

White smoke out the tailpipe on the first start of the day, especially on cold days, is normal. That doesn’t preclude a head-gasket problem, but is not evidence for one. The expansion tank symptom, hard to say, as how that function is accomplished varies from car to car. I know on cars with just a radiator , opening the cap and hearing a hiss when the engine is warm would be normal, b/c the cooling system is pressured a little beyond atmospheric when the engine is warm. Suggest to take a look at the coolant in the expansion tank when the engine is warm and running? See any bubbles coming up? Does rev’ing the engine make even more bubbles? If so, that could be evidence of a faulty head gasket.

@Nick_Law suggest the OP delete this thread and focus on your other thread you have going on the same issue with your Saab

thank you for your detailed response!

@Nick_Law You now have 3 threads going about this Saab . Did you recently acquire this thing and are paranoid about it. Your expansion coolant tank should have marks on it so you don’t need to open it very often. Checking oil on a regular basis like once a week is good. If the oil level increases or starts looking like anything but oil then you can worry.

If you keep revving this car when cold, a blown head gasket is going to be the least of your problems.

STOP revving it, unless you’re trying to kill it.