Coolant / engine temp senders

[Twinturbotr7]

Could someone tell me what the difference / purpose of these senders ?? They both obviously protrude into the water ways so they both monitor coolent temp , is one for the gauge on the dashboard and one for the ecu ???
Thanks Nick

[DaveEFI]

There are lots of variations. Most of the inlet manifolds I've seen with those two sensors have one for the ECU, and the other is a thermotime switch for the cold start injector on the flapper system. The dash gauge one being beside the thermostat.
The later manifold I have here has only one drilling - for the ECU sensor.

[Twinturbotr7]

This is what I always thought was the hot wire manifold as its got the later style green stripe injectors and it 3.9 with NO extra injector

[Twinturbotr7]

The reason I need to know is because im going to be running stand Alone ecu I've also modified my inlet manifold to be a forward facing throttle body and need to move the twin terminal sender as it's in the way So was going to cut off and move it so it's not in the way while I'm at it I was going to compleatly remove the other (single connection) sender and it's boss and weld the hole up as I assumed it wasn't needed ???? I'm also fitting a boss so I can use an original tr7 sender for the dashboard gauge
so anyone else out there that knows what these senders are ????

[unstable load]

What engine is that from? If it's a Land Rover, then have a look at the RAVE manual for that model, they are pretty good manuals.
Can be found here...
http://www.d-lander.com/manuals/

[Twinturbotr7]

What engine is that from? If it's a Land Rover, then have a look at the RAVE manual for that model, they are pretty good manuals.
Can be found here...
http://www.d-lander.com/manuals/

Thanks for that I will have a look
Mine is hrc2616 I've googled that and I looks like it's either a 3.9 Range Rover classic or p38
4.0 Range Rover both seem to use the same part I will have a look and see what it says for both on that manual
Thanks Nick

[garrycol]

The left hand sender is for the water temp gauge and the right hand sender is sensor for the coolant temp input to the ECU. I have the same basic layout on my RV8 4.6.

Garry

[DaveEFI]

The left hand sender is for the water temp gauge and the right hand sender is sensor for the coolant temp input to the ECU. I have the same basic layout on my RV8 4.6.

Garry

That sounds like sense. On my SD1, the dash coolant gauge varies from about 90 to 100c depending on traffic conditions. A log from MegaSquirt using the inlet manifold sensor shows a much more consistent temperature. The SD1 has the dash gauge sensor beside the thermostat.

[stevieturbo]

Yep, as others have said, 1 wire is for the dash gauge, 2 wire is for the ecu. Probably Lucas SNB802

[Twinturbotr7]

Thanks for that guys I'm going to scrap the single wire sender relocate it and fit a tr7 sender for the dash so hopefully it should read ok ish , and move the 2 wire sender so it won't foul the throttle body , thanks again everyone