Mg overheating
Discussion
ZR 1.4 petrol
This is temperature gauge:
https://youtu.be/UuTbRWSTfak
It's had new head gasket and passed block test now.
Had new water pump.
Looks like it's just had new temp sensor near front nearside of block.
However guage does exactly same whether the sensor is plugged in or not. If it's not plugged in, and for the video it was not plugged in, the fan stays on all the time as you'd expect it to so ECU obviously recognising it's not connected up.
Coolant in top radiator pipe hot and cold in lower pipe.
Not sure if it's actually overheating or not!
Seems to rise near red on acceleration then fall on dipping the clutch. You can see the correlation between engine speed, road speed and temp in the video...
Any pointers guys?
No heat in cabin either which I presume is the heater control valve behind engine but can't see that affecting engine temp..,
This is temperature gauge:
https://youtu.be/UuTbRWSTfak
It's had new head gasket and passed block test now.
Had new water pump.
Looks like it's just had new temp sensor near front nearside of block.
However guage does exactly same whether the sensor is plugged in or not. If it's not plugged in, and for the video it was not plugged in, the fan stays on all the time as you'd expect it to so ECU obviously recognising it's not connected up.
Coolant in top radiator pipe hot and cold in lower pipe.
Not sure if it's actually overheating or not!
Seems to rise near red on acceleration then fall on dipping the clutch. You can see the correlation between engine speed, road speed and temp in the video...
Any pointers guys?
No heat in cabin either which I presume is the heater control valve behind engine but can't see that affecting engine temp..,
looks like a short or bad connection in the temp circuit. The rate of change is too extreme for it to be thermostat.
Run the engine and wait till the thermostat opens and both hoses are warm.
Check there isnt another sensor in the rad for the fan - Im assuming you dont have A/C (fans can be kept on if running).
Run the engine and wait till the thermostat opens and both hoses are warm.
Check there isnt another sensor in the rad for the fan - Im assuming you dont have A/C (fans can be kept on if running).
sensor disconnected means its not the component causing the issue.
Remove the fuse from the fans and see if they stop - they should.
You probably have an intermittant bad connection/corrosion causing high resistance fooling the gauge. If the fans are triggered with the same switch, the false reading will bring the fans in.
Remove the fuse from the fans and see if they stop - they should.
You probably have an intermittant bad connection/corrosion causing high resistance fooling the gauge. If the fans are triggered with the same switch, the false reading will bring the fans in.
Hi all
I've had more time on this and do think the temp gauge is actually correct.
At middle laser heat gun reading about 100 and as guage went up laser also started showing about 110-120.
I'm replacing the thermostat as a precautionary measure although it tested ok ish.
But what's strange is the coolant in the coolant reservoir is cold and the thin/small overflow pipe on the reservoir has no coolant coming back.
On removing thermostat i tried to turn the water pump through the hole and couldn't indicating the shaft is fine and should be spinning with the engine to circulate coolant. Plus it's a new pump.
Any pointers?
I've had more time on this and do think the temp gauge is actually correct.
At middle laser heat gun reading about 100 and as guage went up laser also started showing about 110-120.
I'm replacing the thermostat as a precautionary measure although it tested ok ish.
But what's strange is the coolant in the coolant reservoir is cold and the thin/small overflow pipe on the reservoir has no coolant coming back.
On removing thermostat i tried to turn the water pump through the hole and couldn't indicating the shaft is fine and should be spinning with the engine to circulate coolant. Plus it's a new pump.
Any pointers?
Have a check of the earth strap on the battery to front slam panel
These rust/corrode and give a bad connection and all sorts of weird shizzle happens
Just fixed this on the Rover 25 (same car) as the connection snapped and caused havoc...
Immobiliser, temp gauge, starting....
New connector crimped on and cleaned surface and all back to normal
Just an idea.
These rust/corrode and give a bad connection and all sorts of weird shizzle happens
Just fixed this on the Rover 25 (same car) as the connection snapped and caused havoc...
Immobiliser, temp gauge, starting....
New connector crimped on and cleaned surface and all back to normal
Just an idea.
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