: Can't find the engine temperature switch.



Bob Tarpenning
11-25-10, 08:53 AM
I guess my first attempt at this message didn't register so I'll try again. I have a 1984 Eldorado Biarritz Convertable with the 4100 engine. I can't find the engine temperature switch that controls the light on the dash. I have a service manual. I have found the coolant temp sensor and the engine metal temp sensor but I can't find the engine temp switch. The manual says it is by the dip stick but I can't find it. Please help.
Bob T

drewsdeville
11-25-10, 12:41 PM
The temp switch is on the rear head near cyl 8.

Sevillian273
11-25-10, 05:09 PM
Engine temp switch and metal temp switch are the same thing. It is where drew describes and it screws into the head. When the temp reaches 360 degrees or so, It turns the light on in the dash. I beleive there is an alarm beep that goes with it.

Bob Tarpenning
11-26-10, 12:59 PM
The 1984 Eldorado engine is mounted front to back not crosswise. The engine metal temperature switch is in the left head at number 7 cylinder. It turns the stop engine temperature light and alarm on at 320 degrees F. The engine temperature switch turns the coolant temp light on at 269 degrees F. These two switches are not the same. The coolant temperature sensor is in the intake manifold near the water outlet to the radiator. It sends data to the ECM. The engine temperature switch is the one that I can't find. If anyone knows where it is located please let me know.
Bob T

drewsdeville
11-26-10, 03:25 PM
The 1984 Eldorado engine is mounted front to back not crosswise. The engine metal temperature switch is in the left head at number 7 cylinder. It turns the stop engine temperature light and alarm on at 320 degrees F. The engine temperature switch turns the coolant temp light on at 269 degrees F. These two switches are not the same. The coolant temperature sensor is in the intake manifold near the water outlet to the radiator. It sends data to the ECM. The engine temperature switch is the one that I can't find. If anyone knows where it is located please let me know.
Bob T

Again, as far as I can tell from my sources, and the other 4.X engines, the engine metal temp and engine temp switches are the same thing...the object threaded into the side of the head, though I'm pretty sure they are all in the LEFT head (left side, from the perspective of the drivers seat looking forward).

The coolant temp sensor and the metal (engine) temp switch is all there is. There is no 3rd unit.

Metal (engine) temp switch:
http://info.rockauto.com/getimage/getimage.php?imagekey=1185544&imageurl=http%3A//info.rockauto.com/Airtex/1T1065.jpg

Coolant temp sensor:
http://info.rockauto.com/getimage/getimage.php?imagekey=87199&imageurl=http%3A//images.wrenchead.com/smartpages/partinfo_resize/DUS/213-52.jpg


You already found both of those, and there is nothing else. That's why you can't find it.

Bob Tarpenning
11-26-10, 05:50 PM
If the engine metal temp switch turns on at 320 degrees and the engine temperature switch turns on at 269 degrees, how can you do that with one set of contacts? If this were correct the coolant temp light and the stop engine light would come on at the same time and that's a little too late. I located the coolant temp sensor and the engine metal temp switch from pictures in the Cadillac factory service manual. They look like the pictures you sent. They talk about the engine temp switch that turns the coolant temp light on at 269 degrees but unfortunately they don't show a picture of the location. My coolant temp light comes on when the key is turned on and goes off when the engine starts (not the stop engine temp light) so I know the bulb is good. Maybe the manual is wrong but you can't operate 2 bulbs that come on at different temperatures from one set of contacts. That switch has to be there somewhere.

quins90lac
11-26-10, 06:17 PM
dose any one know where i can find the plug its self for the metal temp sensor

Sevillian273
11-26-10, 06:38 PM
I'll betcha the ECM turns on the coolant temp light when it sees 269 degrees from the coolant temp sensor. This would leave the 'one set of contacts' for the metal temp switch. Try to find the 'phantom' switch at rockauto.com.

drewsdeville
11-26-10, 08:10 PM
:yeah:

quins90lac
11-29-10, 11:30 PM
not that hard to find it under the sub section Electrical-Lamp & Socket it's listed as Temperature Switch. but i still can not find the electrical connector mine came loose and came in contact with the exhaust pipe and kinda melted it . It still works but i would still like to replace it with a new one. Or is this one of them parts the you spend all day at the salvage yard to find one decent one.

Bob Tarpenning
11-30-10, 09:21 AM
At least someone admits there is a temperature switch. I looked in my '84 Factory Service Manual but it doesn't have a subsection called electrical lamp and socket. The book says it has a dark green wire and it is circuit 35 but doesn't say where the switch is located. One place in the book says it is near the dipstick and another place says it is in the front of the engine. Where is yours? My engine is mounted front to back and yours is croswise but the switch should be in the same place on the block.