Help! Engine coolant sensor snapped off!

mcc

Original poster
Member
Apr 8, 2012
49
My Envoy's running cool (up to 3 ticks to the left of center, confirmed by Torque) so I decided to replace the thermostat + engine coolant temp sensor. I was taking the old one off with an offset 18mm flare nut wrench and this happened:

View attachment 21506

:eek::eek: How do I get this thing out? Should I get it towed?
 

Attachments

  • DSCF9669.jpg
    DSCF9669.jpg
    60.8 KB · Views: 16
  • DSCF9671.jpg
    DSCF9671.jpg
    62.5 KB · Views: 14

McGMT

Member
Jun 17, 2012
621
Oh you poor poor man, feel for ya... One thing about it, it wont leak... But, do you happen to have a set of easy outs? Could try those, hit it with some penetrating oil, work the easy out around in there, if that don't work I have another suggestion but you have to be extremely careful with it if you try it...
 

mcc

Original poster
Member
Apr 8, 2012
49
Unfortunately my tool selection here is sparse, I'm home with only this car and I don't have a set of easy outs. I've sprayed it with PB blaster (I did before I started working on it as well).

In my panic after this I didn't even realize that it's not going to leak. Should it be safe to drive without it for 3 1/2 hour trips? I need to get to work tomorrow... If not, how could I rig up the new sensor to report high enough temps for the car to enter closed loop?
 

Phantom

Member
Jun 17, 2012
277
mcc said:
My Envoy's running cool (up to 3 ticks to the left of center, confirmed by Torque) so I decided to replace the thermostat + engine coolant temp sensor. I was taking the old one off with an offset 18mm flare nut wrench and this happened:

View attachment 7635iView attachment 7636

:eek::eek: How do I get this thing out? Should I get it towed?

Left handed drill bit? Spray it with some penetrating oil and do not try to get it out quick. Take your time. That's what I did when i broke two bolts in the block when changing the water pump.. Good luck!
 

McGMT

Member
Jun 17, 2012
621
mcc said:
Unfortunately my tool selection here is sparse, I'm home with only this car and I don't have a set of easy outs. I've sprayed it with PB blaster (I did before I started working on it as well).

In my panic after this I didn't even realize that it's not going to leak. Should it be safe to drive without it for 3 1/2 hour trips? I need to get to work tomorrow... If not, how could I rig up the new sensor to report high enough temps for the car to enter closed loop?

Ummmmm, a resistor put in place of the old sensor would trick it if you knew what resistance 200 deg was.... A short trip would be ok to get it where you gotta go without the sensor but I don't know about a few longer trips, would hate to see ya take out your converter...
 

mcc

Original poster
Member
Apr 8, 2012
49
I DO have a large variety of resistors and soldering equipment on hand. If I knew the resistance I could easily rig something up.

Edit: I don't see how I could get my drill in there :sadcry:
 

Mark20

Member
Dec 6, 2011
1,630
If you heat the old one to about 200F you can get a resistance measurement on the thermister.
 

MAY03LT

Member
Nov 18, 2011
3,422
Delmarva
mcc said:
I DO have a large variety of resistors and soldering equipment on hand. If I knew the resistance I could easily rig something up.

The temp vs resistance chart in the service manual states that:

177ohms = 212degrees
241ohms = 194degrees

So a resistor in that range should do what you're looking for.

Did the sensor turn at all before it snapped?
 

Wooluf1952

Member
Nov 20, 2011
2,663
Milwaukee, Wisconsin
MAY03LT said:
Did the sensor turn at all before it snapped?

^^^ That.

The brass is soft. You may be able to wedge a screwdriver in there and get it to back out.
 

Wooluf1952

Member
Nov 20, 2011
2,663
Milwaukee, Wisconsin
mcc said:
I DO have a large variety of resistors and soldering equipment on hand. If I knew the resistance I could easily rig something up.

Edit: I don't see how I could get my drill in there :sadcry:

If you get the right size extractor, you should be able to remove it without drilling.
 

mcc

Original poster
Member
Apr 8, 2012
49
Thanks everyone for your fast/quality replies. I was able to get about 1 full turn before it snapped.

Based on the ranges MAY03LT posted I was able to pick a variable resistor and set it for the 190-195* range- I verified it with Torque. At this point I'm too worried about messing it up further to proceed. I'm having doubts about getting the lower thermostat bolt out and I have to accept the limits of my inexperience with these sorts of jobs. I'm having someone drive it in to a local independent shop tomorrow to get the coolant sensor, thermostat and new hoses installed professionally. It'll be $$$ but at least I won't mess it up to the point of having to get it towed :bonk:

Update: It didn't start this morning so I set it to 120*, let it idle for a bit, revved it to ~2k to warm it up and set it to 160*F. I've left instructions to let it idle for 2-3 minutes every 45mins to keep it warm until it can be taken in in a few hours. Thankfully the shop's only 7-10 minutes away so it won't run long in open loop.
 

mcc

Original poster
Member
Apr 8, 2012
49
Ok, the damage is in- $270 for:

-Extract the coolant temp sensor
-Replace coolant temp sensor and thermostat (both Delco)
-Replace upper/lower radiator hoses (Gates) and clamps (Precision Brand)
-1 gal coolant

Add $90 for the parts from Amazon and the total for the job comes to $360. Not bad at all!
 

Forum Statistics

Threads
23,444
Posts
639,446
Members
18,668
Latest member
Zee0719

Members Online