Changing the ECTS Coolant Temp Sensor (with pictures)

[auxmike]

This is how I changed my coolant temp sensor in a 1995 SL2 Twin Cam with auto tranny and ABS.
I bought the sensor from a Saturn dealer,this way I got the special threadlocker on it already to install.I would not buy an aftermarket version of this part because of this.

DISCLAIMER!:I just took pictures of what I did one day.
I don't suggest you actually try this at home yourself.Hire a real mechanic.I am not responsible if you try this and get hurt or ruin your car doing this!

First I made sure the car is DEAD COLD!You can't do this with hot antifreeze,it will burn a guy badly!

BEWARE THE AIRBAG SENSORS!:
If I have an older Saturn I would notice two stickers on the black metal front frame.I don't bang stuff there!

Ice cold engine off , I opened the hood.
I unclip the 4 airbox clips by the radiator end of the intake.

http://img55.photobucket.com/albums/v169/auxmike/DSCN0543.jpg
I Squeezed together the two prongs of the spring clip that holds the intake to the throttle body.
It locked open to allow removal from the throttle body.That clip stays on,BTW.
http://img55.photobucket.com/albums/v169/auxmike/DSCN0560.jpg
I removed the breather hose from the valve cover.Then remove the plastic intake.
http://img55.photobucket.com/albums/v169/auxmike/DSCN0545.jpg
I Found the ECTS under the EGR valve.Some cars have two sensors,it's the lower back one I could not even see.I had to feel for the two "high" spots on the connector bell and squeez/pull to get it off.See below later on details how this is done.
http://img55.photobucket.com/albums/v169/auxmike/DSCN0550.jpg

[auxmike]

After I got the connector off,this is how it looked in the car.I could'n't see this so I stuffed the camera in there.
http://img55.photobucket.com/albums/v169/auxmike/DSCN0549.jpg
I used a 13mm deep socket to unscrew the old sensor,1/4 inch drive preferred.I didn't unscrew it all the way though!

http://img55.photobucket.com/albums/v169/auxmike/DSCN0551.jpg
I quick unscrewed the connector the rest of the way by hand,then had the other new sensor in hand ready to screw in.Coolant WILL come out of the hole,so the quicker I got that new one started ,the less a mess I had.Note the red stuff on the threads.That's the VERY important threadlocker that comes on the dealer part.

http://img55.photobucket.com/albums/v169/auxmike/DSCN0552.jpg
Tightened down the new sensor with the 13mm socket.Spec is 71 INCH pounds,that's not a lot!I did not overtighten,but didn't leave it so it will wiggle out later either.
I just turned it till it felt snug enough to stay put.Their is threadlocker on the dealer part sensor,red stuff.
http://img55.photobucket.com/albums/v169/auxmike/DSCN0551.jpg

[auxmike]

I Checked old sensor and connector.If the connector is slimey inside,one might want to buy a new one.This is optional,but recommended if one has green slime in connector.
http://img55.photobucket.com/albums/v169/auxmike/ECTSandconnector.jpg
Here's the connector pack I can buy from the dealer,cost $26,comes with instructions.
http://img55.photobucket.com/albums/v169/auxmike/connectorpack.jpg
Here's new all brass next to old cracked brown resin ECTS.What's that PCV valve doing in there?
http://img55.photobucket.com/albums/v169/auxmike/ECTScomparo.jpg
This is how the sensor goes in/out.I squeeze it on the black just above where my thumb is.I did'nt squeeze the longer "horns".They are part of the locking system.This is the sensor resting in position.
http://img55.photobucket.com/albums/v169/auxmike/DSCN0554.jpg

[auxmike]

This is the sensor locked in.Note how the "Flats" on the brown part lines up with the black part you squeeze.
http://img55.photobucket.com/albums/v169/auxmike/DSCN0556.jpg
I couldn't see any of this,so I had to feel it to get it back on right,the connector that is.
Thus the illustration outside of the hidden area it resides in.
Once the sensor is in and connector reattached,reinstalled the intake.
http://img55.photobucket.com/albums/v169/auxmike/DSCN0557.jpg
I gently squeezed again the spring clips at the throttle body while pressing down the lock tab with a screwdriver.Eased off the clips gently.
http://img55.photobucket.com/albums/v169/auxmike/DSCN0558.jpg
Pressed closed the 4 clips for the airbox.
http://img55.photobucket.com/albums/v169/auxmike/DSCN0559.jpg
Checked the antifreeze level,topped off if needed.Checked for any tools left around engine bay or hood!
Started car,checked for any leaks.
This is what I did today,thought you might like to see.
Remember,this is show and tell,I'm not teling you to try this yourself.

[HomeBase]

THANK YOU!

I need to replace mine on my 96 SL2. This will help me tremendously!

THANK YOU! THANK YOU!

GREAT JOB!!!!

[Tiger]

Beautiful! Thanks for the great picks and directions! :p

[dcp]

Very good information,THANKYOU!

[wolfman]

Very good pictures. I will only interject that the sensor with the SINGLE yellow wire going to it that IS visable in all those pictures is NOT the ECTS. That is the sensor for the GAUGE in 95' and earlier cars. If you look at the picture where the poster is using the ratchet wrench with the extension on it, it kinda points (as he is tightening it in the picture) to where the ECTS IS, BELOW and to the RIGHT of where the one wire gauge sensor that can be seen in the pictures is located. 96' and UP cars will NOT have the gauge sensor visable in these photos so there is no chance of making an error and removing the wrong one.

[auxmike]

Thanks Wolf!
Yes,it's the two wire.I would hope folks would realise that by the way I mentioned you can't really see it.
Any advice just how tight to go for the 99% of people out there who don't have a torque wrench in inch lbs.?
I don't like to hammer it all the way home due to the fact it's brass and dished at the end.When I feel resistance,I ease up on it.The threadlocker seems to hold it still quite well.

[wolfman]

The "feel" of a fully seated ECTS is very similiar to a spark plug. When you feel the resistance increase to the point that you can no longer turn it by hand, THEN carefully use the socket wrench to continue. When you feel a marked increase in resistance to turning the wrench, about another 1/2 turn MAX will do. DO NOT wrench it down with all your strength. You can also pull off the socket and feel for the gap between the hex head of the sensor and the engine. When that gap is gone, the sensor is fully bottomed. I wish your excellant pictures had been added to the "How To" instructions I had posted months ago...they would work quite well hand in hand, though your instructions are right on the money.

[auxmike]

Wolf,feel free to "steal" my pics and add them to your description as you see fit.Not a problem.
All I ask is credit for the pics.
Mi casa es Su casa!:cool:

[Spazie]

I feel handy!! I just did this all by myself. First time I've ever done something mechanic-ish on my car without my brother's supervision. Thanks for the pics, they were a great help!!

[Razorbak]

ttt

Can one of the moderators please make this thread a sticky? :?:

(Same for wolfman's ECTS thread.)

Thanks.

[ndsaturn]

quik question. the etcs on my 93 saturn is brass with a black plastic end. which one is this? old or new style, or aftermarket ? ty

[sierrap615]

thats the new and improved style.

[123SVT]

I tried this BUT at the last step I couldn't get the conector on right now it read nothing on my temp gauge.... :dizzy:


Ryan

[sierrap615]

i know it doesn't look directional, but i'm sure it is, try fliping it 180 degrees

[Luke]

Spazie
I feel handy!! I just did this all by myself. First time I've ever done something mechanic-ish on my car without my brother's supervision. Thanks for the pics, they were a great help!!

That should strongly support the suggestion that you continue to work on your car--it can only gett better, & surprise you even more. :yes:

[emptypockets]

Awesome auxmike! I need to do this on my car and I don't think we even have a 13 mm socket let alone a deep well. Thanks for the how-to.

[romac]

We just got our ECTS in for her 96 SC1 5spd. How much do these instructions vary from that? Anything else to look out for? Is this something we can do on our own?

[KPatrick]

Just curious why the replacement in the first place, what were the symptoms? I suspect mine being bad, 94 SC2. It misfires until the engine warms up. No codes and replaced the O2 sensor and EGR valve last year.

[Luke]

Fm >> KPatrick <<

>Just curious why the replacement in the first place, what were the symptoms? <

Just do a search on ECTS and you'll come up with considerable & detailed information on it; for Saturn upgraded the unit, as the old ones were cracking, resulting in a mis-read being sent to the computer, with the engine running colder and using more fuel, due to the mis-read.

[JerryHughes]

Hi all,

I read somewhere that after the sensor was changed that the PCM B fuse should be reset by pulling that out for about 15 seconds. Is that true? If so, that may be my problem! Thanks,

Jerry

[auxmike]

Never heard this myself,but it could be true....

[Razorbak]

Never heard this myself,but it could be true....

It's in wolfman's ECTS thread...

You "should" reset the PCM after changing this (or ANY sensor) this does NOT require any special tools, just disconnect the NEG battery cable for about 15 secs.

Changing the ECTS (Engine Coolant Temp Sensor) (http://www.saturnfans.com/forums/showthread.php?t=24003)

[sierrap615]

you can disconnect the NEG cable, but i perfer pulling the PCM B fuse, its easyier and you don't lose your radio presets.

[reemoe]

Please forgive, as it sounds like it's super simple, but where and how do I go about pulling the PCM B fuse?

Thank you!
Ryan

[Luke]

Fm >> Ryan <<

>where and how do I go about pulling the PCM B fuse? <

After opening up your front hood, there should be a black rectangular fuse box, located in front of the battery, on the driver's side. The top of the box should be secured by a small circular screw. Simply loosen it, and lift up the top of the fuse box. On the underside/inside of the top, you'll see where each of the fuses sit.

[reemoe]

Thanks, Luke! So I just find it, take it out with my fingers, I'm guessing, and put it right back in?

[Luke]

Yep; I leave it out for atleast a "minute". Just to insure that the memory is cleared :D

[green]

Auxmike:

In the photo with the ratchet it shows one end of the connector (black cap cover) going to the sensor, where's the other end going? My 95 SW1 temp gauge isn't working. The photo with the part in the bag is exactly (with 2 butt connectors) what I bought from Saturn but they give me instructions.
Could you give me instructions (photos?) on how to install the connector.
Thank You very much.

[auxmike]

Green,
You crimp the wires to the original wires from the cars harness.You heat up the butt connector's ends to shrink/seal them.
Hope this helps some..... :D

[green]

I installed the single wire temp gauge sensor connector. Now the temp gauge is working again. But the engine light remains on and the horn doesn't work. This happened after taking my 95 vehicle from tranny shop. The auto parts store only checks vehicles 96 or newer. Do I have to buy a scan tool that will only work on a 95 or older Saturn or GM car?

[madpogue]

The auto parts store only checks vehicles 96 or newer. Do I have to buy a scan tool that will only work on a 95 or older Saturn or GM car? Lucky for you, NO. It's way easy with an OBD-1 ('95 and back) car. This how-to entry (http://www.saturnfans.com/forums/showthread.php?t=28570) describes how to acquire the code with a paper clip, and even deciphers the codes.

That's why the store only does '96 and later; they're OBD-2, which require a scan tool.

BTW, since this is no longer really part of the "how to" for changing the ECTS, you might want to start a new thread in the regular "S-Series Tech" section.

[rixter]

Wow is all that needs to be said about this post. Awesome. Thank you. :yes:

[kickarse]

Where;d you guys buy yours? How much did you spend?

[Tiger]

I got mine at Saturnparts.com. Less then $10 for the ECTS, but $8.50 for shipping. So I bought a Transmission Filter to split the shipping charge and reduce overall cost.

[mainedvd]

There is (was) a little cap that went over the electrical connector to my ECTS on my 97 SL2. I lost it, can't find it anywhere. Is this really necesary? It does cover the wires, but I have heard no mention of this cap anywhere. Would the dealership provide me with a new one, and for how much?

[jdhimie]

The pictures and explinations are outstanding! Thanks a million times.

[auxmike]

Thanks all.
I never thought this would be so popular.
It was fun documenting the job. :arr:

[globasco]

Hey guys-- silly girl question.

Would a broken ECTS Sensor cause my fan to not turn and, in turn causing my poor lil saturn to overheat when idling/in slow traffic??? :tear:

[Tiger]

If the ECTS is not working properly, the fan will not turn on. Also, fans go bad. Also, it may be good to check for a blown fuse, at least that is what I would do. No fan will cause overheating problems at idle/in slow traffic. If you turn the AC on, the fan should turn on. If it is coming on with AC, the fan and the fuse are probably good. ECTS may be the culprit. That is my understanding. I am a silly Social Worker. The experts here can direct you better.

[edlee]

Thanks for all of the information, everyone. I changed the engine coolant temperature sensor myself with the jacking-up-the-driver-side procedure. I have a 1999 Saturn SL1 with slightly under 30,000 miles on it. The removed temperature sensor did not seem to have any cracks in it, but it is good preventive maintenance, as wolfman or someone else wrote.

[edlee]

I would also like to add that I found it hard to remove the air intake on my SL1 because of that narrow tube that branches off the middle of the main air intake. So what I did instead was remove the battery as someone else suggested.

If I had to do the procedure again, I would place a towel or rag under the ECTS to catch the half a cupful or so of coolant that leaks out as someone else photographed.