1984 ECM coolant Temp sensor (Page 1/1)
Nickoman APR 30, 10:41 AM
Hi Gang,
I have a Coolant temp sensor that I am suspicious of. I would swap it out with a new one, but the connectors for modern senders are different. So, my question is two parted haha.
1. Does anyone have a data sheet for the old style ( pigtail ) temp sensor? I have written a python script that will check temp ( from an arduino temp sensor ) to the recorded resistance values of the coolant temp sensor.

2. Q # 1 would answer this question, but in case no one has the answer. If swapping the connector on the vehicle, Is the modern ( 2 prong) temps sensor a direct plug-n-play besides the connector splicing?

Thanks in advance,
Nick
theogre APR 30, 11:08 AM
Ω chart for this See my Cave, Sensors Quick Ref

Buy new sensor w/ new plug as pigtail "kit." Is made to replace old style one not longer made.

Install w/ joints solder and "water proof" shrink tube w/ glue inside to seal.
Need 25w or higher solder iron/gun and rosin flux and lead base solder. Lead free can work but needs more heat.

Any other method often get crap in joints that adds resistance and make sensor "lie" to ECM.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

Nickoman APR 30, 12:19 PM
Holy Cow What a wealth of knowledge you and your page are! I will check the resistance values. if its Faulty I will follow the guide!!

Thank you!
phonedawgz MAY 02, 08:09 PM
Make sure the one you are replacing has two wires on it. One Black and one Yellow.
fierosound MAY 03, 12:21 PM

quote
Originally posted by Nickoman:

Hi Gang,
I have a Coolant temp sensor that I am suspicious of. I would swap it out with a new one, but the connectors for modern senders are different.



Temp sensor for computer had not changed.
Temp sender for gauge has not changed.

Sounds like someone has them mixed up.
What exactly are you trying to fix?



------------------
My World of Wheels Winners (Click on links below)

3.4L Supercharged 87 GT and Super Duty 4 Indy #163

[This message has been edited by fierosound (edited 05-05-2020).]

Nickoman MAY 18, 01:28 PM
[QUOTE]Originally posted by fierosound:


"Temp sensor for computer had not changed. "

The sensor plug has totally changed since the 84 model.

Ended up figuring out I had a faulty O2 sensor ( tons of carbon build up)
fierosound MAY 18, 03:12 PM

quote
Originally posted by Nickoman:

[QUOTE]Originally posted by fierosound:


"Temp sensor for computer had not changed. "

The sensor plug has totally changed since the 84 model.



Haven't had a problem buying the right one for my 84 Indy.
I don't recall needing a new connector. Maybe GM had different ones over time.

[This message has been edited by fierosound (edited 05-18-2020).]

Nickoman MAY 18, 03:39 PM

quote
Originally posted by fierosound:


Haven't had a problem buying the right one for my 84 Indy.
I don't recall needing a new connector. Maybe GM had different ones over time.







https://www.youtube.com/watch?v=diUdDmr66dc Check this out. Must have been a mid 84 change I have the before change haha
Gall757 MAY 18, 05:00 PM

quote
Originally posted by Nickoman:

Check this out. Must have been a mid 84 change I have the before change haha



That video is totally confusing.
theogre MAY 18, 06:44 PM
ECT in the Tstant tube for ECM HAS Changed w/ Metripak ends starting w/ 87 cars and no-one makes the old style one since.
For a short while after could get NOS old ones but still had old iffy plugs causing problems w/ replacement sensors.

NTK EF0074 have the sensor and pigtail but Don't use crap splices shown.

If you want other brands of sensors...

Just the pigtail is:
WVE 1P1006
FOUR SEASONS 37231
under Electrical-Connector > Temperature Sender / Sensor Connector (84 doesn't list FS one. Other years does.)

84
AC cars has 2 senders for the Rad Fan and 1 for dash gauge/light.
non AC cars has 1 for each.
All are on the block or head near Tstant pipe.

Oil pressure switch/sender is right of the distributor.