General Cooling System Servicing: Notes
CAUTION:
Pressure may build up fast. Release any excess pressure above the upper limit of pressure cap specifications or cooling system damage may result.
If needle does not fluctuate, race engine a few more times and check for water at tailpipe. Excessive water would indicate a faulty head gasket, cracked block or cylinder head near exhaust ports. Next, remove oil dipstick and if water globules appear in the oil, a serious internal leak is indicated.