• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

Known problems from a bad ECT Eng cool temp sensor. List please

  • Thread starter Thread starter Yellow302
  • Start date Start date Apr 25, 2005

Yellow302

Member
Mar 2, 2003
789
2
19
NJ
Apr 25, 2005
#1
  • Apr 25, 2005
  • #1
My temp gauge has been going passed R before it goes to closed loop. Then the temp varrys from between N-O then up to R again. My fan seems to come on early and late, or the guage is on R and the fan isn't on. The fan realy isn't my problem right now.

I am more worryed about my car's tranny locking up before it enters closed loop. I am thinking my car thinks its hot when its cold and cold when its hot. The temp guage raises then drops the raises quickly.

I have a 192 Termo right now that I put in for the winter. I wonder if replacing the ECT that pulgs into the intake manifold will help. I thinks is like $4 from napa.
 

1slow95

Founding Member
May 16, 2002
1,797
3
48
ohio
Apr 25, 2005
#2
  • Apr 25, 2005
  • #2
That sounds like what mine was doing. A new ECT should fix it.

BTW, If you turn the defrost or A/C on, the fan should kick on. That's what I did when mine started getting too hot.
 

Yellow302

Member
Mar 2, 2003
789
2
19
NJ
Apr 25, 2005
#3
  • Apr 25, 2005
  • #3
where would i get an new ECT, autoparts store or a ford dealer?
 

WhiteDevil

New Member
Feb 4, 2003
2,717
0
0
San Diego
Apr 25, 2005
#4
  • Apr 25, 2005
  • #4
Ok for one the temp gauge in your car and your ECT sensor are two different things. Your temp gauge is just a little sending unit in ur lower intake manifold. Your ECT is in the black coolant hard lines on the pasenger side of your intake manifold. Second how are you veryifying that you are in closed loop???
Mostly what when you have a bad ECT sensor like i did you will get a rough idle and poor drivability when the car is on a cold start up. Thats what i have and it was cured by my new ECT sensor. But your temp gauge and ECT are two different things so i tink your are getting confused.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Apr 25, 2005
#5
  • Apr 25, 2005
  • #5
The pcm adds or removes fuel & spark based off ECT.

Later
Grady
 

rude_life

Member
Mar 30, 2005
372
0
16
Apr 25, 2005
#6
  • Apr 25, 2005
  • #6
WhiteDevil please can you elaborate on where the ECT is again..i asked on here where it is located yesterday and everyone told me it plugged into the lower intake manifoldI knew what they were talking about but i knew there was one in a heater or coolant line or something. Is it actually INSIDE the line or is it plugged INTO the line or something?? I am having the same symptoms that you mentioned above and i would like to get it taken care of but i cant find the ECT!! My chilton is about as clueless on the topic as i am..Please help
 

1slow95

Founding Member
May 16, 2002
1,797
3
48
ohio
Apr 25, 2005
#7
  • Apr 25, 2005
  • #7
This is the ECT I believe.
 

rude_life

Member
Mar 30, 2005
372
0
16
Apr 25, 2005
#8
  • Apr 25, 2005
  • #8
Thats the one that screws into the water outlet on the lower intake manifold
 

Zero Signal

Active Member
Feb 24, 2003
2,633
2
46
Tucson, AZ
Apr 25, 2005
#9
  • Apr 25, 2005
  • #9
Yeah thats the one. Mine had a bad harness that made it read wrong and keep the fan from switching on. Check the wireing harness/plug before buying a new sensor.
 

Yellow302

Member
Mar 2, 2003
789
2
19
NJ
Apr 25, 2005
#10
  • Apr 25, 2005
  • #10
well i do have a ruff idel / drivablity problems with the car right now, until its warm. I belive my ECT is the problem. If my temp guage was way off then i would suspect the guage or my t stat was sticking.

Where can I get an ECT sensory any way, I checked on napa's web site and they said it was like 4 bucks
 

Hef5.0weisen

20+ Year Stangneter
Mar 5, 2004
574
4
28
NorthWest Florida
Apr 25, 2005
#11
  • Apr 25, 2005
  • #11
any parts store should carry them
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Apr 25, 2005
#12
  • Apr 25, 2005
  • #12
you can also check the thermistor at vaious temps to see if it is calibrated.

good luck.
 

rude_life

Member
Mar 30, 2005
372
0
16
Apr 25, 2005
#13
  • Apr 25, 2005
  • #13
Are there two ECT Sensors???!!
 

Hef5.0weisen

20+ Year Stangneter
Mar 5, 2004
574
4
28
NorthWest Florida
Apr 25, 2005
#14
  • Apr 25, 2005
  • #14
nope, just one, it's circled in an earlier reply
 

rude_life

Member
Mar 30, 2005
372
0
16
Apr 25, 2005
#15
  • Apr 25, 2005
  • #15
Im confused Somebody else (WhiteDevil) said its in the black coolant lines running alongside the passenger side lower intake manifold...??
 

WhiteDevil

New Member
Feb 4, 2003
2,717
0
0
San Diego
Apr 25, 2005
#16
  • Apr 25, 2005
  • #16
The ECT(engine coolant temp) sensor - is circled in the picture that low5.0 posted, that is the temp device that sends the temp info to your cars computer, so that it can adjust your idle spark and timing based on the temperature of your engine.

The Temp Sending unit - is on the front driverside part of your intake manifold. That only feeds information to the gauge in your dash board. It has nothing to do with the operation of your car.

help any?
 

1slow95

Founding Member
May 16, 2002
1,797
3
48
ohio
Apr 25, 2005
#17
  • Apr 25, 2005
  • #17
rude_life said:
Im confused Somebody else (WhiteDevil) said its in the black coolant lines running alongside the passenger side lower intake manifold...??
Click to expand...

It is in the black coolant line on the pass. side lower intake.
 

1slow95

Founding Member
May 16, 2002
1,797
3
48
ohio
Apr 25, 2005
#18
  • Apr 25, 2005
  • #18
Maybe this will help a little. It's a zoomed in pic of the circled area in my previous pic.

 

rude_life

Member
Mar 30, 2005
372
0
16
Apr 25, 2005
#19
  • Apr 25, 2005
  • #19
Id say that pretty much cleared things up. Thank you guys
 

rude_life

Member
Mar 30, 2005
372
0
16
Apr 25, 2005
#20
  • Apr 25, 2005
  • #20
You guys are awesome
 
You must log in or register to reply here.

Similar threads

S
Fuel ‘88 GT Runs Rich Cold — Fixes Itself When I Unplug Sensors (ECT, MAF, O2, etc.)
  • Sufarry
  • Nov 6, 2025
  • Fox 5.0 Mustang Tech
Replies
12
Views
1K
Fox 5.0 Mustang Tech Nov 9, 2025
Mustang5L5
SURGING IDLE / NO IDLE CHECKLIST FOR 1999–2004 MUSTANG GT (4.6L 2V) - Work In Progress
  • Noobz347
  • Aug 30, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
0
Views
1K
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
SURGING IDLE / NO IDLE CHECKLIST FOR 1996–1998 MUSTANG GT (4.6L 2V) - Work In Progress
  • Noobz347
  • Aug 30, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
0
Views
1K
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
Engine 1990 LX 5.0L EFI Mustang Fuel Management Problems - HELP!
  • 5.0LXStanger
  • May 25, 2025
  • Fox 5.0 Mustang Tech
  • 2 3
Replies
45
Views
2K
Fox 5.0 Mustang Tech Jul 11, 2025
5.0LXStanger
H
New kid on the block
  • HydraX
  • Mar 22, 2025
  • The Welcome Wagon
Replies
17
Views
997
The Welcome Wagon Mar 22, 2025
HydraX
H
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?