Coolant Temp Sensor

Sean486 · #1 08-26-2009, 08:26 AM

I just checked my codes and see that I am displaying a Code 21 Coolant Temp Sensor. I did a few searches and learned that it is located on the rear of the engine and not too expensive.
I was hoping that someone could just let me know how difficult it is to change that. I'm pretty inexperienced but if it is something that I can get at easily I'll give it a shot.

Hocrest · #2 08-26-2009, 08:34 AM

Not too bad, the only thing you need to remove to get access is the plastic H-6 Cover.

Standing on the drivers side, look under the the rear of the intake manifold, you'll see two sensors going into the coolant crossover.One sensor has one wire, that feeds the coolant temp gauge. The other has two wires, this one feeds the ECU, this is the one you want to change. to replace it, just unplug the connector and you'll need a deep socket (iirc 19mm or 3/4") to turn it out.

Make sure the car is cold, if it's hot the results when removing the sensor would be similiar to removing a rad cap on a hot engine.

SoCal LS-L · #3 08-26-2009, 11:42 AM

Yarp, it is eeeeeeeeeee zeeeeee. I would recommend (if you have a multimeter) testing the new sensor to make sure the ohms reading is within range. Some here have had problems with "new" sensors being total garbage.

At 68F room temp, the ohms should be between 2000-3000, if its a little warmer the reading will be slightly lower maybe in the high 1000's.

Almost forgot...check the harness too, the wire bends over 90 degrees from the main harness and sometimes the insulation will crack and short the wires, or the plug itself is dirty.

Sean486 · #4 08-26-2009, 03:48 PM

Thanks, I'll take a look at it tonight.

Sean486 · #5 08-26-2009, 08:29 PM

So is this the kind of thing that I can get at a parts store or should I go OEM at the local dealer?

SoCal LS-L · #6 08-26-2009, 08:49 PM

I got mine from Autozone for $26, works just fine. Not sure what the dealer charges.

dcarrb · #7 09-14-2009, 05:56 AM

Quote:

Originally Posted by Sean486

So is this the kind of thing that I can get at a parts store or should I go OEM at the local dealer?

What you'd get from Subaru is probably the same as you'd get from any parts house. This is not a Subaru-manufactured item.

Think I paid about fifteen bucks at O'Reilly's, but that was a few years ago.

dcb