For the first time my car started to overheat today and its only around 75 degrees out !!!!

No changes to motor or cooling system and it NEVER overheated or got about 210-215 last summer in 100 degree weather.

Got off the freeway and got gas and noticed that the temp was 220.... started to drive away on city streets and it kept climbing to around 230-240.... pulled over........ I have the dual Spal fan and only one of the fans was on..... turned my heater on and started driving again.......got on the freeway and it got down to 180... off the freeway and it started to climb again but got home with it under 220.

Got home and started to check stuff out... the Spal fans are acting funny.....

If I turn the power on, but dont start the car, temp guage around 220, the fan doesnt always kick on..... sometimes it does right away, sometimes it will after about a minute.

If I remember correctly they used to kick on right away if the temp was above 180 and I turned the power on

Start the car and temp 210 and climbing... neither fan comes on.....

The guage works, so I assume the guage sender works okay... does this sound like an issue with the relay kicking the fan on or the actual fan temp sender unit??? It seems like the fan operation is real sporadic....

How can I test the sender vs the relay ???

[ 03-12-2005, 04:10 PM: Message edited by: DRJDVM ]

If the sender is just a switch that closes when it gets to the set temperature, (one wire sender) you can pull the lead off the sender and ground it to the block. The relay(s) should get picked up and start the fan. If the sender has two wires (one wire from the ignition switch or fan switch, the other to the relay) you can just jump the two terminals. That should connect power to the relay(s) and the fan should start.

The sender in the block has 1 gray wire hooked to it.... it looks like it splits (inside the wire loom)since 2 gray wires come out of the loom with 1 going to each of the 2 relays....

I'm pretty sure one fan comes on at 180 and the other around 210 or so.......