1. Several possibilities if the car is not really overheating:

• Faulty temperature gauge sender unit (see image)
• Faulty instrument temperature gauge

If you have a multimeter, you can read the resistance of the gauge sender unit. Unplug the Red wire from the sending unit. Measure the resistance of the sending unit between the positive terminal of the sending unit (tip of the sending unit) and engine ground. When it is cold should be about 142 ohms. If the engine is at operating temperature, it should be about 32-49 ohms.


2. You may want to pick up an Infrared temperature gauge like TexasHonda suggested. With an Infrared temperature gauge, the coolant temperature at the thermostat housing; where Fan Switch A also is located, should be above 194 degrees to trigger the fans. -- You can also take readings at multiple places to compare the temperature.

 

Excellent insight guys, thanks . I had just replaced the sender a few months ago so I wasn't thinking that it may not be working correctly. I do have a multi meter so I will start with that first tomorrow, and ill have to order temperature gauge. Btw, Auto zone claims that they only make thermostats 170 or 180 F, (Maybe that's just what They carry).

 

I've never had much luck w/ aftermarket thermostats. Too slow to warm up and operating temps may not match specification. For thermostat, OEM part is way to go.

good luck

 

I am still waiting for the temp gauge that I ordered. The AutoZone sensor was jumping all over when I tested it, from 50-195 ohms and wouldn't settle anywhere. I put in a used one that I had around and it sat at 70. (the old one that I had replaced was the same. I don't know if this is significant info.)
Are cooling systems in the newer accords this complicated? I love my wagon, but its turned into more of a hobby than a daily driver. Ive been driving a 2003 element lately while I 'play'with the wagon.

 

1. The gauge sender unit should not have been jumping around when you took a resistance measurement. With the meter set to read resistance (ohms), one lead would be touching the tip of the sender unit, the other meter lead would touch body ground or battery ground.

The resistance (ohms) at the sender depends on the coolant temperature. Did the instrument gauge in the dash change with the old sender unit?

2. You can pick up a infrared laser thermometer like this one at Home Depot for about $30. This can tell you temperature in your engine compartment and other places.

Ryobi -4 to 600-Degree Non-Contact Infrared Thermometer-IR001 - The Home Depot

Harbor Freight has a different style one for about $20.

3. For your 2003 Honda Element, the cooling system is not really more or less complicated; just different.

For the cooling fans, the Element has only one fan switch unlike the 91 Accord with two switches. The first attached picture shows the location of the fan switch, which is at the bottom of the radiator.

On the Element, the coolant temperature gauge is controlled by the CPU built-in to the gauge assembly. The CPU receives coolant temperature information from the ECM/PCM. The ECM/PCM receives coolant temperature information from the ECT sensor. The second attached picture shows the location of the ECT sensor.

 

Btw: We generally suggest testing first before any replacement; but, you probably already know that from your previous threads where we replied. However, it is your decisions that will give you piece of mind.

 

Tried to figure this out on my own but I give up. Am I reading this wrong?
black is on battery post, red is on tip of sender.
im afraid im not as experienced with these multi-meters as id like. I read up as much as I could online but didnt find much on cars. Car is overnight cold btw.

 

You probably are doing it right. Your photo show it at about 180 ohms cold. Is this the old or new sender?

Although the service manual states 142 ohms cold, the sender unit may still be okay.

Have you taken a reading when it is warmed up?

 

This is an old one out of the parts car, the new one was hard to get a consistent reading on-it ranged between 129 and 142. I took a video of the readings on the meter bouncing around, pretty crazy, but it wont upload ):
No, I have not let my car warm up yet since I put that one in, (I wanted to make sure I was testing correctly anyway.) I will do a warm test tomorrow and also see how the gauge behaves.

 

I let it warm up, No indication of over heating on gauge! Yay! The meter read 66 ohms after the car was running in the drive way 15 min. I will take it to work and give it another test when I arrive.