Autozone/ advanced auto usually has antifreeze that goes with either kind. I suggest that.
into the coolant reservoir on the passenger side of the engine bay by removing the cap
R-134A
134a.
if its clear its water and needs to be removed and replaced with Antifreeze. You can get pre-diluted or strait antifreeze which you must dilute yourself 50/50. The kind needed is in your car manual or on the resivoir cap the way those buckets are set up it will look clear sometimes
could be a damaged hose or seal. You probably need a mechanic to replace it.
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How can I replace the headlamp on a 2000 Saturn SL1
It depends on what is wrong with it. Take it to a good garage.
Around four quarts, give or take a few ounces.
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Probably just over a gallon - buy the 50/50 premix and just fill it up