Hi all,
I took my E9 out for a quick spin today (spring has finally arrived ... sort of :lol: ) and discovered that the water temperature gauge has developed some sort of problem - an electrical one I believe.
This is how the problem manifests itself: When the car is running the temperature gauge shows the engine being 'hot', i.e. the needle is sitting somewhere between horizontal and the red field, i.e. above the horizontal. This is the case regardless of whether the car is driving (plenty of cold cooling wind) or idling.
Last year I replaced the water pump, the thermostat, the viscous clutch and all hoses, i.e. I know the cooling system is in good shape. Furthermore I know the engine is not hot, because when I switch off the engine and then switch the ignition key back to Position I (i.e. I don't start the engine), the temperature gauge shows the correct temperature, i.e. the needle is somewhere under the horizontal position. In other words, the temperature gauge is only showing 'too hot' when the engine is running.
The needle also displays another very odd behaviour which leads me to believe that there may be a short somewhere. When I switch off the engine, the water temp needle jumps all the way to the top of red field and stays there for approx. 2 seconds
Here's what I have tried:
Initially I thought it was a temperature sender problem, so I swapped the temperature sender with another one which I had lying around. After that I swapped the actual instrument which I also happen to have a spare of.
Finally I tried to connect the temperature sender directly .. and with a separate wire to the temp. instrument ... the gauge is still acting up
:x
Oh by the way I also vented the cooling system to make absolutely sure there were no air pockets in the system.
I suppose it could still be a faulty temp. sender even though I fitted another one however isn't it unlikely that 2 senders should cause the same 'behaviour'? As I said it looks like an electrical problem, but what electrics are involved other than the wire running directly from the temp. sender to the instrument?
Any thoughts on this annoying problem will be most appreciated
Cheers
I took my E9 out for a quick spin today (spring has finally arrived ... sort of :lol: ) and discovered that the water temperature gauge has developed some sort of problem - an electrical one I believe.
This is how the problem manifests itself: When the car is running the temperature gauge shows the engine being 'hot', i.e. the needle is sitting somewhere between horizontal and the red field, i.e. above the horizontal. This is the case regardless of whether the car is driving (plenty of cold cooling wind) or idling.
Last year I replaced the water pump, the thermostat, the viscous clutch and all hoses, i.e. I know the cooling system is in good shape. Furthermore I know the engine is not hot, because when I switch off the engine and then switch the ignition key back to Position I (i.e. I don't start the engine), the temperature gauge shows the correct temperature, i.e. the needle is somewhere under the horizontal position. In other words, the temperature gauge is only showing 'too hot' when the engine is running.
The needle also displays another very odd behaviour which leads me to believe that there may be a short somewhere. When I switch off the engine, the water temp needle jumps all the way to the top of red field and stays there for approx. 2 seconds
Here's what I have tried:
Initially I thought it was a temperature sender problem, so I swapped the temperature sender with another one which I had lying around. After that I swapped the actual instrument which I also happen to have a spare of.
Finally I tried to connect the temperature sender directly .. and with a separate wire to the temp. instrument ... the gauge is still acting up
:x
Oh by the way I also vented the cooling system to make absolutely sure there were no air pockets in the system.
I suppose it could still be a faulty temp. sender even though I fitted another one however isn't it unlikely that 2 senders should cause the same 'behaviour'? As I said it looks like an electrical problem, but what electrics are involved other than the wire running directly from the temp. sender to the instrument?
Any thoughts on this annoying problem will be most appreciated
Cheers
