2004 Malibu LS - Coolant Temp Sensor replacement [Archive] - Chevy Malibu Forum: Chevrolet Malibu Forums

: 2004 Malibu LS - Coolant Temp Sensor replacement


acevans79
12-17-2010, 12:04 PM
Hello,

I have a 2004 Malibu LS 3.5l V6. My check engine light is on and I notice that since it got cold out the car has been starting rough for the past few days.

I hooked up a engine light computer and the code said that the coolant temperature is lower than the thermostat gauge says it is.

I have bought a coolant temperature sensor and just need instructions as how to replace it. I am handy but by no means a mechanic so if you can include a diagram that would be great!


Thanks

Starship
12-17-2010, 05:13 PM
The ECTS is item 3 in the drawing http://cid-54465800aad91b49.office.live.com/self.aspx/pub/Right%20Rear%20of%20LX9.GIF. You're supposed to drain the coolant to the level below the sensor, apply the sealer (P/N 13246004) to the sensor threads, and then tighten it to 15 ft-lb. With that said, if it were registering really low temperature, the problem is probably a broken circuit (most often inside the electrical connector). There should be a 5V on one of the terminals with the key on and ground on the other terminal.

chevyguy8893
12-17-2010, 07:18 PM
Hello,

I have a 2004 Malibu LS 3.5l V6. My check engine light is on and I notice that since it got cold out the car has been starting rough for the past few days.

I hooked up a engine light computer and the code said that the coolant temperature is lower than the thermostat gauge says it is.

I have bought a coolant temperature sensor and just need instructions as how to replace it. I am handy but by no means a mechanic so if you can include a diagram that would be great!


Thanks

Did the code happen to be P0128, coolant temperature below thermostat regulating temperature? If not then ignore the rest. If so, it is more than likely going to be the thermostat. If you are going to be replacing the temp sensor you might as well replace the thermostat to cover that base instead of loosing more coolant in the future if the code comes back after replacing the sensor.

acevans79
12-17-2010, 08:12 PM
Thanks for the information folks. I replaced the coolant temperature sensor and everything seems to be back to normal. In fact, I am actually getting better gas mileage now according to the info on the radio.

Thanks Again!

Starship
12-17-2010, 09:20 PM
You're quite welcome and thanks for the update.:D

Anglerking
03-16-2011, 04:54 PM
I too have the same problem. Tried to go to the web address given to see the diagram but get the message that the particular address has either been moved or deleted.:eek:
Would appreciate getting a link to an engine diagram showing both the ect sensor and thermostat.

Thanks, guys.:)

acevans79
03-17-2011, 11:30 AM
The coolant sensor is located on the drivers side of the car on the rear of the engine block. I will take a picture and post it shortly. Very easy to replace just make sure that you drain the coolant first before you attempt to remove and replace it.

acevans79
03-17-2011, 11:56 AM
http://i1119.photobucket.com/albums/k630/acevans79/COOLANTTEMP.jpg

http://i1119.photobucket.com/albums/k630/acevans79/COOLANTTEMP2.jpg

Anglerking
03-21-2011, 09:17 AM
Thanks a ton for the photos. Will post again after completing the change.:)

Anglerking
03-21-2011, 02:01 PM
Thanks a ton for the pictures.:D Would also appreciate if you would post a picture of the related thermostat . I understand it would be better to change the thermostat too at the same time. Is this correct?:confused:

Thanks again.:)

flathead
08-08-2011, 03:48 PM
I own a 2007 malibu maxx with the 3.5 litre engine. Recently the engine temp. gauge stopped working and the coolant fans are constantly running. Also check engine light came on. I disconnected negative battery cable to reset light and installed a new coolant temp. sensor. Temp gauge worked and cooling fans worked correctly for approximatey 100 miles until my wife started the car after work today and temp. gauge is not working and cooling fans are constantly running again ,but no check engine light yet. Also hooked up my code reader to see what the code was , but all that comes up on the screen is linking error! Can anyone help me please?

howie6907
11-18-2014, 01:05 PM
I have a 2004 malibu LT V6 with 50,000 K. Got the check engine warning and when I scanned got the P0128 warning. Are you suggesting to replace the thermostat first (most likely) and sensor second. If I have to drain to replace the thermostat and sensor should I just replace both parts. It is the original thermostat (10 years old!)

Drunken Elvis
11-18-2014, 01:19 PM
The previous post is more than 3 years old, so you are not likely to get a reply from them.

As for your problem, what does the temp gauge indicate? Can you check the engine temp with another instrument? A point at temp gun? I would suggest replacing the thermostat only, but if the job is large and you only want to do the job once, it might be best to replace both items at the same time.

More info would help and your financial situation and your level of mechanical ability also come into play. Do you have the time to tinker with it?

Many of these decisions are yours to make.