The vehicle is a 1984 DL 1800 wagon, carbureted. According to

 

http://www.obd-codes.com/trouble_codes/subaru/1983-1988-subaru-carbureted.php

 

, this is either a coolant temperature sensor or idle-up solenoid problem.

 

 

Now, when it says coolant temperature sensor, it isn't talking about the fan switch is it? Because that thing on my car has been out for years. I've nabbed two of those things from Subarus in a Pick N Pull, and they were all bad too. I know the wirings good because ive just connected the two wires and the fan runs whenever i turn the key on, which sort of solves the problem but is still annoying. I suspect that others here may have had a similar experience.

 

But about the idle-up solenoid. I only have a crappy Chilton manual as I said before, and I can't find a damn thing about an idle-up solenoid. I checked the Automotive Dictionary at http://100megsfree4.com/dictionary and it tells me that the idle-up, AKA fast idle solenoid controls the throttle in an automatic choke during acceleration. This makes sense because my acceleration has been pretty rough recently.

 

But the diagrams of the carbureters in my Chilton manual for both the Hitachi and Carter-Weber don't show a fast idle or idle up solenoid. I'm not even sure which of the two my car has. I've tried looking, but its just a mess trying to make sense of these exploded diagrams.

I just checked my Haynes repair manual and it said coolant temp sensor. This is the sensor that is near the thermostat on hitachi cars and sends the signal to your gauge. I had the same number come up on my car awhile back. Replace the sensor and your ECS light should go off.

The coolant sensor you are looking for is for the ECU, not the temp gauge. It lets the ECU know how warm the coolant is so it can adjust the fuel mixture as needed. The sensor may have two wires going to it. The sensor for the gauge has one wire to it and it won't trigger a code if it is bad.

The coolant sensor you are looking for is for the ECU, not the temp gauge. It lets the ECU know how warm the coolant is so it can adjust the fuel mixture as needed. The sensor may have two wires going to it. The sensor for the gauge has one wire to it and it won't trigger a code if it is bad.

 

Excellent! That sounds about right because my mileage has been pretty crappy recently. ALSO! I found out I have neither the Carter-Weber or the Hitachi. I have a DCZ328-504C/505C as found on the old Chilton manual on page 210.

 

So is this coolant temperature sensor located on the carbureter or the engine or the radiator? I am checking my manual to try to find it right now.....

 

ALSO! I know that the fan switch has two wires going to it, but it isn't that one right? I think that is the only one connected to the radiator....

I think the sensor is located on the engine. The sensor for the fan is a temperature switch, it is either open or closed. The coolant sensor is a thermistor and changes resistance as temperature changes.