1976 -1979 1980 Cadillac EFI Air - Coolant Temperature Sensor replaces 1609968

[79 Eldorado]

1976 1977 1978 1979 1980 Cadillac EFI Air - Coolant Temperature Sensor replaces GM 1609968 /AC Delco 213-188 / EL31 Hewitt Industries PN 021-104

This is a replacement for GM PN 1609968 also known as AC Delco PN 213-188. Two sensors are used per car; one for the coolant and one for the intake air. Both are threaded into the intake manifold. If you have a 1976 to 1979 Cadillac (through 1980 in California) and it has fuel injection this should be the correct sensor.

If the coolant temperature sensor goes bad you will have issues with cold starting. I researched the sensors with help on this site and I replaced the original sensing device with a modern alternative with the intent of improving the durability. Electronically the resistance curves follow extremely closely in the most critical temperature range. The wire is multi-strand all Copper wiring (not Copper clad Aluminum). The sheathing is the best automotive grade available. The sensor housing as well as the bulb is brass despite the copper appearance of the bulb. The bulb is brazed to the housing from the inside using Silver containing solder. Efforts have been made to allow the internal sensing element to maintain thermal freedom.

Especially the coolant temperature sensor should be checked if you are having cold start issues. These are easy to check before buying a replacement but the connectors are sometimes brittle. If you find yourself in the need of a replacement connector (either half) I now have them as well. I have one of these cars myself and had a cold starting problem. Thanks to members on this site I quickly learned how to check these and found that my coolant sensor had failed (open circuit and infinite resistance). The car started after changing just the coolant sensor but I later found the air temp sensor failed with unusually low resistance (about 40% low). One side of each of my connectors was very brittle. If you do not care a lot about an authentic look I can also offer both sides of a more modern weatherpack connector with the terminals etc.

If you prefer to buy through eBay I do have them offered there but you will get a better price through this forum. Please post here if you are interested and send me a PM through the site. On eBay search for “1609968” and look for the same photos as you see here.

Thank you for looking and any questions are welcome,
Scott

76 77 78 79 80 Eldorado Biarritz Seville Sedan DeVille Coupe Brougham

[Buick39]

I bought two sensors from Scott for my 77. That was a very smooth transaction with a lot of information and he could even provide connectors for the sensors.

The car runs like it should now and I can remove the potentiometers I added to emulate the resistance for the disconnected sensors.

Back to normal!

Thank‘s a lot Scott for opening this thread and the help the Seville owners will get from it.

Ulrich

[76eldo]

That’s a fantastic product and a big help for early FI owners.
Does my 80 Eldo use these sensors?

[79 Eldorado]

Hi Brian,
If it was a California emission car it likely still uses them in 1980. What engine do you have in your 1980? In California if it was a 5.7L it should still use the same part as the 1979. If it is a 5.7L I can tell you where to look because at least the coolant sensor is fairly visible once you open the hood. It's to the vehicle left (driver side) of the thermostat housing a couple of inches from the left head (or on your right if you have the hood open and you are looking at the front of the engine). The air sensor is in back of the throttle body and easier to see with the air cleaner removed.

Scott

[76eldo]

I have the 368 with throttle body injection

[79 Eldorado]

I think that's likely the newer version of EFI then. 1980 seems to be the cross-over year. Likely more people will see the post if we post it within the thread I created when I was developing the sensor. That thread is here:
http://forums.cadillaclasalleclub.org/index.php?topic=152760.0

The 368 was new for 1980 so I suspect they may have introduced the new EFI with it...that would be my guess. Is your car starting and running fine? There is a really nice trouble shooting matrix in the 1976 EFI diagnosis manual. From what I've learned on this site that book covers 76 to 79 well so for 1980 there is probably a similar book.

Scott

[76eldo]

Starts and runs great.

Brian

[79 Eldorado]

Sounds good Brian. I confirmed the 368 in 1980 used the DEFI or what I was referring to as the newer generation EFI. Only California emissions cars in 1980 still used the earlier system.

Scott

[Kiwichris]

Hi Scott I'm keen to get one of these sensors sent here to New Zealand. I've got a 79 Fleetwood Brougham with the injected 425. There's no parts here for Cadillacs unfortunately. I've sent you a PM. Thanks. Chris.

[79 Eldorado]

Thanks Chris. I replied to the PM.

[Kamusenue]

Ok I am doing what you guys are telling me and this is just not working ---can the damn webmaster please make this site where you can just upload a damn PICTURE  PLEASE-------------------   dam it.   This is frustrating as hell.

[79 Eldorado]

Example detailed for prior post.... see attached for instructions. You will not see the photo in your preview but if you "post" it should appear.

Regards,
Scott
PS: I'm not an admin but you posted on one of my topics in the "For sale" section.

[Kiwichris]

Bought a coolant temp sensor from Scott for my 79 Fleetwood Brougham FI 425. After the cold start issues I was having, I've just had the sensor arrive here in NZ, put it in the car and she started first turn of the key from cold, excellent work Scott, and thanks for all your help.

[AFI]

If anyone is interested, I have NOS coolant and air temperature sensors, and a couple of used ones as well. Also 2 NOS EFI throttle body assemblies with cold start heater valve, TPS. Also 2 used ECU's for the Seville. Also a complete 1978 Seville trip computer system including wire harness and all components, diagnostic manual, operator manual. Also reed/rpm switches, distributors, NOS high pressure chassis pump, NOS fuel filter housing/mounting, filter elements, NOS green top fuel injectors, used green top fuel injectors, AND a Kent Moore 'blue box' Diagnostic Tool and a Kent Moore 'scan' tool for retrieving a broke down EFI system that enables driving to a repair facility.

Also NEW factory service manuals for 76-79 Seville, Fisher Body Manuals, owner manuals.....OEM all new. No reprints!

[79 Eldorado]

Hello everyone,
I'm adding a picture of the most recent sensors. I needed to tool the housing as the ones I was using are no longer available so I took it as an opportunity to move to 1-piece brass machined housing and bulb as opposed to brazing the separate brass bulb into the housing. Please see attached.

I also recently released a replacement for the EFI FIV Fast Idle Valve sometimes referred to as a choke heater. It replaces the following Delco Remy, GM and Bendix PNs It replaces GM PN 1606776, GM PN 1617956, GM PN 1628898 and is also known as Bendix PN 1181290 and Bendix PN 1181835. They are an improvement over the originals and allow your car to move from fast idle to normal idle in a reasonable amount of time as the Cadillac Engineers intended.

Here's the link and I will also add one photo here:
http://forums.cadillaclasalleclub.org/index.php?topic=162989.0

Scott

[khatalidavid@gmail.com]

Scott,
  I am planning on installing fuel injection on my 76 eldo covertible. Would I need these sensors to operate correctly or do the appropriate ones come with the new installation. If they're not too expensive, i should probably get some. Please advise and if necessary, stand-by to sell me one each, thanks.

Dave Calkins
4805444077