Temp Sensor making hard start

[ryno1121]

I have disconnected my temperature sensor and install an aftermarket gauge. I read that the sensor sends informaion to the CPU during start up. Does anyone know if this is true. I have new plugs, wires, ect. It is very hard to start, dies after a few seconds and is sluggish when it will idle. Once the engine has a small amount of heat it runs like a champ. Any help?

 

Thanks

Ryan

 

1991 4.0L with auto trans.

[Eagle]

Which temp sensor did you disconnect, the one at the back corner of the head or the one in the thermostsat housing?

[ryno1121]

Thermostat housing

[bigalpha]

I believe that the t-stat sensor is for the computer and the back of the head is for the gauge in the cluster.

[ryno1121]

I'm going to buy a new one tomorrow and give it a try. I will let you know how it works out.

 

Thanks for the help.

[HOrnbrod]

I have disconnected my temperature sensor and install an aftermarket gauge. I read that the sensor sends informaion to the CPU during start up. Does anyone know if this is true. I have new plugs, wires, ect. It is very hard to start, dies after a few seconds and is sluggish when it will idle. Once the engine has a small amount of heat it runs like a champ. Any help?

 

Thanks Ryan 1991 4.0L with auto trans.

 

On your 91, the temp sensor on the thermostat housing sends information to the ECU all the time, not just during startup. If you have it disconnected, you'll never get out of open loop. Put the original sensor back in the thermostat housing and hook up the ECU input wire like it was originally. The stock temp gauge sensor is located on the back of the head, left side, near the firewall. You can safely remove this sensor and install your aftermarket gauge in it's place with no ill effects.

[ryno1121]

Put the new sensor in and it started right up. The idle was much better also. When I did the swap I thought this only controled the light on the dash. Lesson learned!

 

Thanks for the feedback.

Ryan