Temp sender problem

[TJC46]

Hi guys whilst doing a few winter jobs i managed to snap the spade of the temp sender [the one in the inlet manifold behind the dizzy].
Now i have used Rimmer bros for various v8 parts, so purchased a temp sender off them, for as they describe a rover 3.9 v8 engine, but im wondering if the original one as fitted by TVR is specific to the caerbont temp gauge.Why am i thinking that,...... well......
My new sender is reading way over 90 degrees, the fans have not kicked in as usual,and just by experience the car is no where near the "indicated" temp.I have a fan overide switch and both fans work fine. I will put a laser infa-red temp gun on it tomorrow to cross check the "indicated" and actual temps but just wondered wether anyone could say for sure that it is, or isnt, TVR specific.thanks Tom.

[Simon says]

Yes the stock sender is TVR specific, you can use the original LR one but you have to wire in a 200ohm variable resistor but the gauge wont be as accurate, however it will still indicate & overheating condition if present and the operating temps indicated will be just fine, I have mine like this and have never looked back for over 4 years now

[Alexdaredevilz]

I think I used a 130 resistor

[plushuit]

TJC46]Hi guys whilst doing a few winter jobs i managed to snap the spade of the temp sender [the one in the inlet manifold behind the dizzy said:

.
Now i have used Rimmer bros for various v8 parts, so purchased a temp sender off them, for as they describe a rover 3.9 v8 engine, but im wondering if the original one as fitted by TVR is specific to the caerbont temp gauge.Why am i thinking that,...... well......
My new sender is reading way over 90 degrees, the fans have not kicked in as usual,and just by experience the car is no where near the "indicated" temp.I have a fan overide switch and both fans work fine. I will put a laser infa-red temp gun on it tomorrow to cross check the "indicated" and actual temps but just wondered wether anyone could say for sure that it is, or isnt, TVR specific.thanks Tom.

I am curious. Hotwire V8s normally have two coolant temperature senders...one behind the dizzy and another (much smaller) on the other side, adjacent to the thermostat. The dizzy sender provides the ECU with the information it needs and the other normally sends its info to the temperature gauge.

[TJC46]

plushuit said:

I am curious. Hotwire V8s normally have two coolant temperature senders...one behind the dizzy and another (much smaller) on the other side, adjacent to the thermostat. The dizzy sender provides the ECU with the information it needs and the other normally sends its info to the temperature gauge.

Hope to help with your curiosity. All together on the rover v8 engines TVR used there are 3 temp senders. One for the ecu, one directly below the thermostat for the dash temp gauge, and the 3rd is the original range rover one which tvr left in situ, which cannot be used as it is, unless you fit some kind of inline resistance as it is not calibrated for the dash temp gauge that TVR used.......At least i think thats correct....hope it makes some sense.

[Simon says]

TJC46 said:

plushuit said:

I am curious. Hotwire V8s normally have two coolant temperature senders...one behind the dizzy and another (much smaller) on the other side, adjacent to the thermostat. The dizzy sender provides the ECU with the information it needs and the other normally sends its info to the temperature gauge.

Hope to help with your curiosity. All together on the rover v8 engines TVR used there are 3 temp senders. One for the ecu, one directly below the thermostat for the dash temp gauge, and the 3rd is the original range rover one which tvr left in situ, which cannot be used as it is, unless you fit some kind of inline resistance as it is not calibrated for the dash temp gauge that TVR used.......At least i think thats correct....hope it makes some sense.

Correct

[Biggles101]

So it begs the question Why do we need the one for the dash, can we not use the same one that the ECU uses? surely this is the important one? So long as this reads correctly then the engine management (If we can call it that!) is performing correctly..