canadian z28

my 98 camaro starting running past the 100 mark on the temp gauge. Just past half. Actually the needle sits just past the last 0. Usually it never goes past half on a hot day. On the highway it tends to climb to that point a bit faster. its never overheated or come close to it. any help would be great.
Sorry so long.

MJK

iTrader: (3)

If its overheating on the highway you probably have a coolant flow issue.That could be a bad thermostat,clogged radiator,old hoses collapsing,missing front air damn (the black plastic fin under the front of your car,its more important than you would think!)

Also air trapped in the system as air pocket can cause overheating problems as well as debris trapped up behind your radiator.

If your car were only overheating when at a stop but starts to cool down when you get up to speed,then that usually tends to be a air flow issue.

Just some ideas to start with...good luck!