Question on coolant temp sensor.

[m3boost]

I know that in order for your temp gauge to be more accurate, the e36 sensor must be replaced with an e30 temp sensor...So here's my question...

Is it only the cluster gauge that sees that sensor? or does your ecu also see it? If your ecu does does rely on those reading too, then it won't be accurate to the ecu knowing that it has different resistance to an e30.

The reason for my question is because I replaced my ecu with a TECIIIR and it's reading off that sensor..my temp stays around 200F according to the tecIIIr... I'm wondering if I need to reinstall the e36 sensor.

[Jean]

There are normally two sensors, one is for the ECU and one goes to the cluster. I imagine you leave the one for the ECU alone (e36 kind).

[MR 325]

The gauge sensor is only for the gauge, doesn't go to the ECU.

[7pilot]

Think of it this way.

The OBD 1 ECU requires the coolant temp sensor.
The OBD 1 coolant temp gauge requires a coolant temp sender.
The OBD1 harness has 2 separate wiring and connectors.
The OBD 2 systems use a combination sensor/ sender unit with a 1 connector engine harness.

m

[samiam3356]

Think of it this way.

The OBD 1 ECU requires the coolant temp sensor.
The OBD 1 coolant temp gauge requires a coolant temp sender.
The OBD1 harness has 2 separate wiring and connectors.
The OBD 2 systems use a combination sensor/ sender unit with a 1 connector engine harness.

m

Trying to envision this,

For OBD1, the block would have two different sensors, 1 obd1 e36 sensor for the dme, and OBD1 brown top sensor for the temp gauge in the cluster.

If I'm correct you can run the brown top sensor with this adapter to satisfy both without tapping the head.
http://www.turnermotorsport.com/html..._ID=TEN9989M50

My question is, wouldn't this be sending the wrong information to the DME since your basically just splicing off the e30 sensor?

hmmmmm, I bet you can only use that adapter on e36 cars. Sorry, not a well thought out post i guess.

TIA

[7pilot]

Trying to envision this,

For OBD1, the block would have two different sensors, 1 obd1 e36 sensor for the dme, and OBD1 brown top sensor for the temp gauge in the cluster.

If I'm correct you can run the brown top sensor with this adapter to satisfy both without tapping the head.
http://www.turnermotorsport.com/html..._ID=TEN9989M50

My question is, wouldn't this be sending the wrong information to the DME since your basically just splicing off the e30 sensor?



hmmmmm, I bet you can only use that adapter on e36 cars. Sorry, not a well thought out post i guess.

TIA

Yes, the TMS adapter splicer is useless for OBD 1 engine harnesses.

m