I tried using the search feature, but it dosen't seem to work.

I have an 86' coupe. I added some coolant a few weeks back when it got cold. I thought I burped the system pretty well, but every now and then the "Low Coolant" light would come on for about 10 seconds and then go off. It would never stay on longer than that. Tonight as I waited at a drive through the temp hit 224 degrees and the aux fan came on as normal. I then waited at a light to turn onto the main road. The temp continued to rise (normally it falls to 205 and then the aux fan shuts off), and as I drove down the main road I could see coolant mist coming out of the passenger side front wheel well. I drove home (as the crow flies I was about 300 yards from the house), and as I got up to speed the temp started to drop.

When I got home and popped the hood there was coolant spray all over the passenger front tire and wheel well on the hood, but none in the engine compartment. I could see where there was fresh coolant around the overflow tank cap as well.

I am wondering if the radiator cap has lost it's spring pressure and is allowing the coolant to run out to the overflow tank?

I topped off the radiator and ran it with the front wheels on ramps and the hood up and the aux fan was able to control the temp as normal.

Any ideas?

 

If you can't see signs of leaks anywhere else, a cap is cheap and a good place to start. A couple years back I was having a problem with mine running hot. On one long trip it started to run real hot about 200 miles from home. Not willing to take any chances, I had it towed home on a flat bed. Took the car to a shop and had them presure check the system -- turned out to be the cap, it wasn't sealing properly.