Coolant Temperature Gauge Failure
Thread Starter
Instructor
Joined: Dec 2005
Posts: 142
Likes: 2
From: Centerport NY
Coolant Temperature Gauge Failure
I have a 1990 a4. The coolant temperature gauge on the dash stopped working. it is flat 0. The other gauges all work fine
I changed the coolant temperature sensor on the intake manifold and it still does not work.
Looking at the Haynes Manual 1 line diagram, it looks like there is something called an
"Engine Metal Temperature Switch" feeding the gauge.
Could this be the problem?? Where physically is this in/on the car??
I have a PCM for less chip in the car.
Help with this one appreciated.
Flatbush 862
I changed the coolant temperature sensor on the intake manifold and it still does not work.
Looking at the Haynes Manual 1 line diagram, it looks like there is something called an
"Engine Metal Temperature Switch" feeding the gauge.
Could this be the problem?? Where physically is this in/on the car??
I have a PCM for less chip in the car.
Help with this one appreciated.
Flatbush 862
Thread Starter
Instructor
Joined: Dec 2005
Posts: 142
Likes: 2
From: Centerport NY
Yes thanks Agent 86-
After researching a little bit I found the correct part and location. The auto parts stores often confuse the temperature coolant "sensor" with the coolant "sending unit" the sending unit is as you said on the passenger side head near the #6 cylinder plug. The sending unit has a blade connection where as the "sensor" is a socket connection at the front of the intake manifold under the Throttle body.
Flatbush 862
After researching a little bit I found the correct part and location. The auto parts stores often confuse the temperature coolant "sensor" with the coolant "sending unit" the sending unit is as you said on the passenger side head near the #6 cylinder plug. The sending unit has a blade connection where as the "sensor" is a socket connection at the front of the intake manifold under the Throttle body.
Flatbush 862
5th Gear
Joined: Mar 2009
Posts: 5
Likes: 1
I have a 1990 a4. The coolant temperature gauge on the dash stopped working. it is flat 0. The other gauges all work fine
I changed the coolant temperature sensor on the intake manifold and it still does not work.
Looking at the Haynes Manual 1 line diagram, it looks like there is something called an
"Engine Metal Temperature Switch" feeding the gauge.
Could this be the problem?? Where physically is this in/on the car??
I have a PCM for less chip in the car.
Help with this one appreciated.
Flatbush 862
I changed the coolant temperature sensor on the intake manifold and it still does not work.
Looking at the Haynes Manual 1 line diagram, it looks like there is something called an
"Engine Metal Temperature Switch" feeding the gauge.
Could this be the problem?? Where physically is this in/on the car??
I have a PCM for less chip in the car.
Help with this one appreciated.
Flatbush 862
Hi there is a sensor on the passangers side of the car close to the back of the motor right next to the back spark plug ,,,That sersor controls the temp gauge the one on the mainifold is just a temp switch check that back senson there is 1 single wire that mounts to it some times that wire gets melted or just gets loose and falls off the ground prong and when the wire falls off the gauge will NO longer WORK as this happens to my 1990 c4 with the L98 motor in it when that wire falls off too it stops sending the temp of the motor to the ECM and turns the gauge off and some times sends a check gauge signal to the info centor on the dash Hope i helped some
Last edited by macatxfl; Jun 12, 2009 at 05:02 PM.
Advanced
Joined: Jul 2010
Posts: 53
Likes: 1
From: Avon CT
Temp. Gauge Failure
I just bought a 1990 Corvette and the Temp. gauge was not working all so . I all so looked at the sender at the front of the engine as that is were Chevy used to put the Temp sender . I would have never looked by the right rear spark plug . Sure enough there it was with the wire disconnected . I reconnected it and now the gauge work's fine . Thanks for the help .
Instructor
Joined: Apr 2008
Posts: 171
Likes: 1
From: west chester pennsylvania
Similar thing is happening with my 92 LT1.
The gauge just randomly stopped working, BUT the digital coolant temp. readout still works.
Could it still be that part on the passenger firewall?
The gauge just randomly stopped working, BUT the digital coolant temp. readout still works.
Could it still be that part on the passenger firewall?
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
The " just a temp switch" is the coolant temp sensor (CTS ) located in the intake at front that sends engine temp to ECM and is a major item in engine control
Sending unit in head only runs the temp gauge
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Advanced
Joined: Jul 2010
Posts: 53
Likes: 1
From: Avon CT
The temperature sending unit in the right head is needed for the analog temperature gauge located in the dash to work . If it worked once and a while the wire connector was loose and now is disconnected . The sender is located next to a spark plug so when changing plugs it gets knocked off .
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
sender for the cluster circled in green.
5th Gear
Joined: Jan 2014
Posts: 5
Likes: 0
Hi there is a sensor on the passangers side of the car close to the back of the motor right next to the back spark plug ,,,That sersor controls the temp gauge the one on the mainifold is just a temp switch check that back senson there is 1 single wire that mounts to it some times that wire gets melted or just gets loose and falls off the ground prong and when the wire falls off the gauge will NO longer WORK as this happens to my 1990 c4 with the L98 motor in it when that wire falls off too it stops sending the temp of the motor to the ECM and turns the gauge off and some times sends a check gauge signal to the info centor on the dash Hope i helped some
Team Owner
Joined: Sep 2003
Posts: 25,385
Likes: 2,737
Cliff - Post #14 is 30 months old and #15 is a very vague inquiry mentioning NOTHING about the car!
POSTER "Tony Velasquez" - What year is your car? It would likely be suggested by some that you post a NEW thread but since you're here mention more information about your car. Year, engine, transmission etc.
You mentioned "stock" - shouldn't be an issue!
POSTER "Tony Velasquez" - What year is your car? It would likely be suggested by some that you post a NEW thread but since you're here mention more information about your car. Year, engine, transmission etc.
You mentioned "stock" - shouldn't be an issue!
Last edited by WVZR-1; Jun 8, 2016 at 02:24 AM.
3rd Gear
Joined: Jun 2016
Posts: 3
Likes: 0
Well its a 87 vette with the 5.7 tuned port engine. My temp gauge is going crazy , but whats so funny is i dont even have it conected i dis conected the one in front an the one on the side because i figured that since i disconnected the temp sending unit an that done nothing it still kept marking it goes from 250 to 299 but mainly stays on 299 can their be another one located some where else
Racer
Joined: May 2014
Posts: 416
Likes: 29
From: diamond bar ca
temp guage
Well its a 87 vette with the 5.7 tuned port engine. My temp gauge is going crazy , but whats so funny is i dont even have it conected i dis conected the one in front an the one on the side because i figured that since i disconnected the temp sending unit an that done nothing it still kept marking it goes from 250 to 299 but mainly stays on 299 can their be another one located some where else
