Question: I hope you can help me. My car's temperature gauge will occasionally go up more than normal. During the past several months I've added water to the radiator because it was low. The plastic tank seems to remain at the correct level even though the radiator is low. What suggestions do you have for me to resolve this? Should I be adding antifreeze?
Answer: This is something that needs to be fully resolved, and right away. Do you notice the higher-than-normal gauge temperature while at freeway or similar speeds, or while driving in stop-and-go traffic? If the rise in temperature occurs only at low speeds, an inoperative or weak cooling fan could be the cause. Higher speed symptoms could be the result of a damaged or missing lower air deflector.
A more likely cause of the intermittent high temperature readings is insufficient coolant. A coolant leak seems likely as you are periodically adding water. A cracked hose, loose clamp, oozing water pump seal or other flaw can also prevent the system from drawing coolant back from the overflow tank as the engine cools down, resulting in the low radiator yet normal or overfull level in the overflow tank.
The bottom line is the system needs a complete inspection, pressure testing and validation of proper cooling fan operation. Please forgive my bluntness, but you're playing with fire to do anything but to confront this issue head on! Engine damage due to cooling system malfunctions is tragic and easily preventable. If you need to buy some time before seeking repairs, be sure to check the radiator level daily and watch that temp gauge like a hawk. Topping off with water isn't a good long-term solution, but will do until you can get this repaired.
Q: My pickup makes a faint squeak, squeak, squeak sound as it rolls forward or backward. It sounds like it's coming from under the truck bed. It's not loud but concerns me. Any ideas?
A: If the noise occurs on smooth pavement (no suspension system movement) my hunch would be a dry/beginning-to-bind universal joint. The joint may not yet be loose enough to detect movement when firmly wiggled. How about using this situation as an excuse to treat yourself to the purchase of a non-contact (infrared) temperature gun? These are super useful and can be purchased for as little as $50, possibly less. Drive the truck for perhaps 20 to 30 miles to warm up the driveline, then shoot each U-joint, their yokes, and the driveshaft itself. If one U-joint is noticeably higher in temperature than the nearby shaft or yoke, it's likely to be your noisemaker (replacement is needed).
Temperature guns are also great for checking tire, brake, and bearing temperatures, comparing upper and lower radiator hose temperature (radiator efficiency), true engine coolant temperature (shoot the thermostat housing), air conditioner duct temp — the sky is the limit!
Brad Bergholdt is an automotive technology instructor at Evergreen Valley College in San Jose, Calif. Readers may send him email at under-the-hood@earthlink.net
