Northstar engine new waterpump&thermostat still running hot but gages reading 194degree autoxray codescout2500 read 1 code (p0118engine coolant temperture curcuit high input whats that

The engine was a new attempt to compete with European models
It has cast iron sleeves in an aluminum block. It is prone to head gasket failure. It also has a habit of running hot because of design issues. Make sure the coolant is correct and full, check the temp using a method other than the dash gauge.

Please click this LINK to read a great article on causes and fixes for overheating problems. I can't post it due to copyrighting. Also DO NOT RUN THIS ENGINE WHEN IT STARTS TO GET HOT YOU WILL SEVERLY DAMAGE IT.

If you have no air in the system, cooling fans & water pump are working properly, and you didn't install the thermostat backwards, you could have a head gasket problem. Also, make sure the gauge is reading correctly, and the engine is actually hot & the gauge is not giving you a false reading.
If you installed the thermostat upside down, it will not open to allow coolant to circulate. This 5-10 minute time frame you give points to a water pump or thermostat.
I hope this helps.

Hi,
A/C increases Engine Temp in two ways.
1, extra 2-6hp load on engine.
2, hot condenser in front of radiator heating air going through cooling system.

A small difference in engine temp can be expected, but if the car is running hot get it sorted out.

The gauge on the dash is not accurate at all, you can get a obd live data monitor or you can test the coolant with the engine running and use a reliable thermometer, ( you take the cap off the radiator and run the engine till it gets hot. You also need to check and see if the thermostat is stuck closed.

Hi there,

Firstly - DO NOT run engine, when guage reads hot, as this will cause costly damage to head gasket & alloy engine head.

The fact that guage takes 1min to read HOT, would confirm the guage IS working properly.

So, other components which are likely to cause hot readings (in this order) are:

- lack of coolant (or leakage somewhere): is there sufficient green coolant at the correct level? Top up mixture to correct level. Repair any leaks.

- collapsed radiator hose: when engine is cold, start engine, then quickly watch both upper & lower radiator hoses to see if either begins to flex inwards (collapse). Replace if either hose is collapsed.

- bad/incorrect thermostat rating : when replacing thermostats, you must ensure it is of the SAME temp rating (they all differ).

- Incorrect Temp sensor rating: the ratings of this sensor must be within manufacturer's spec's.

- bad waterpump: the engine relies on the waterpump to distribute the coolant throughout the entire system. If waterpump is faulty, coolant will not flow quick enough, causing overheating.

If you still believe all of the above components are OK, then have your cooling system "pressure tested". This test should be done, before looking further at other electrical components.

Cheers,

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If the engine is getting hot enough it sounds like the flow through the heater core is restricted. When it is hot turn the heater on and feel the radiator hoses. One should be real hot and the other a little cooler, not much. Try taking the heater hoses off and run water from a garden hose through them. Run both directions and maybe it will break something loose. You won't lose much antifreeze by unhooking the heater hoses.

check or change the thermostat it could be stuck open thats why its all ways running cold

is the water pump, belt and tensioner OK? its not where you think it is. its on the drivers side of the front cylinder head.

1. Check the level you filled the coolant to...If you overfilled it this will happen. 2.  Did you add the correctly diluted antifreeze? 3. Check to be sure the radiator is unobstructed