93 ECT Sensor

[Nirajorel]

Hi all,

This is my first post and I’ve been snooping around here for over a month now trying to fix my idling issue on my 1993.

Today, I was in process of switching out my ECT sensor(ECM) and to my surprise, when I installed the new one, my temp gauge did not glove. Took it out, reinstalled it, the temp went up but it’s only going up just above the first line.

I put the old one back thinking it might just be the new one and the old one also did not record a temp. Looked at the wiring harness and realized that the harness is exposed, wire showing.

My question is, obviously I plan to fix the wires but could this be the root of my idling issue? Also, I thought these had a separate temp sensor that goes to the temp gauge, is there a correlation between the two?

 

[Nirajorel]

Go up* NOT glove.

 

[Irish Reiver]

There are 2 seperate temp sensors. One for the guage and one that feeds the ECU. If you have an ODB1 capable reader (Toyocom) you can see what temperature reading the ECU is getting. The guage has a flat spot built in so once the engine reaches temp it will just stay in the same place. Of course if your engine over heats it will also let you but after the damage has been done.

 

[Nirajorel]

There are 2 seperate temp sensors. One for the guage and one that feeds the ECU. If you have an ODB1 capable reader (Toyocom) you can see what temperature reading the ECU is getting. The guage has a flat spot built in so once the engine reaches temp it will just stay in the same place. Of course if your engine over heats it will also let you but after the damage has been done.

Yep. Luckily I noticed it 5 min during warm up as I was trying to see if my idle improved then noticed the temp didn’t go up.

The one I replaced is the one above the oil filter around the 2 o clock position.

 

[Kernal]

For future searches: head sensor locations

A

Post in thread 'Need help identifying sensors'

Sep 19, 2014

There are 4 sensors in this photo, all inline.

Sensor 1 (leftmost) is front knock sensor. Only one cable goes from it. Sensor 4 (rightmost) is back knock sensor. Also needs one cable.

Both middle sensors are yet to be determined by someone else. I suspect the temp sensor is one of them.

Sensor 1 is NOT the knock sensor, but the ECT (engine coolant temperature) Sender gauge. The knock sensor is not in the picture. It is located above & to the right of the oil filter, looking at it from the drivers side of the engine bay. Sensors left to right: ECT sender gauge, ECT Cut switch...

• AJACK

• 

 

[FZJ80 TN 93]

Hi all,

This is my first post and I’ve been snooping around here for over a month now trying to fix my idling issue on my 1993.

Today, I was in process of switching out my ECT sensor(ECM) and to my surprise, when I installed the new one, my temp gauge did not glove. Took it out, reinstalled it, the temp went up but it’s only going up just above the first line.

Were you able to resolve your “idling issue “?
My 93 has a low/ruff idle and I’m looking for a possible common failure. So far I have replaced the spark plugs, spark plug wires, cap, and rotor, which didn’t really help any.

The manual points to the ECT as a possible cause, but it looks to be a pain to get too plus you have to drain the coolant and remove it to test it.

 

[Irish Reiver]

A low or rough idle is likely caused by a vacuum issue. Have you checked the main air intake tube for cracks?

 

[Fj80oregon]

Were you able to resolve your “idling issue “?
My 93 has a low/ruff idle and I’m looking for a possible common failure. So far I have replaced the spark plugs, spark plug wires, cap, and rotor, which didn’t really help any.

The manual points to the ECT as a possible cause, but it looks to be a pain to get too plus you have to drain the coolant and remove it to test it.

Just replace it, and no need to drain the coolant if your just swapping in a new one.

 

[FZJ80 TN 93]

A low or rough idle is likely caused by a vacuum issue. Have you checked the main air intake tube for cracks?

Thanks. The main air tube that runs from the MAF to the throttle body looks new. Some of the other rubber lines look old and cracked.

Not looking forward to hunting down a vacuum leak on this engine with all vacuum lines and actuators Toyota used.