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Is the temp going up quickly or slowly?

Have the faces on the dash been changed or the dash been pulled apart? This requires the needles to be taken off and sometimes they do not go back on in the same place.

Is the undertray on?

Have you replaced the thermostat?

Coolant re-route?

What about the Thermostat sticking and getting hot then releasing and dropping temp to right level?????

Might be worth a try also you have not mentioned radiator cap - has the cap and system been pressure tested??

those two little often overlooked (and cheap) items can cause a world of difference to cooling system operating temps

M@

Don't go doing coolant reroutes and stuff until you've worked out the problem, the stock system works fine in most situations.


Start cheap and work up to more expensive stuff.

Coolant - is there enough (don't just look in the overflow, check the radiator is full)
Radiator cap - replace it, they're like $10
Bleed the system - might be air in the head
Thermostat - replace it, it may be sticking, about $20
have the rad core flushed - might be clogged with sh*t, get it cleaned (try a cleaning additive, if that doesn't work, get it done properly by a radiator shop)

when buying the flush, DO NOT BUY STOP LEAK, only buy radiator flush.
The stop leak works by basically clogging stuff up, it's only of use in a dire emergency.

I had similar a few years ago, was the thermostat new thermostat all good

the small hose that runs off the thermostat housing and returns to the water pump is there so that water flows over the t stat element. if this hose gets blocked, the t stat wont work correctly as the water flow over the element is not sufficient