I'm a girl & know next to nothing about cars. I was driving and my temperature gauge went over towards the "H". All the coolant/water was empty. Mechanic showed me that my water pump was spewing out everything. He replaced my water pump. I thought I was good. However, now when I drive only a about 30 minutes the temperature gauge starts moving to the "H", the oil gauge goes to the right and the battery gauge starts moving to the left. This happens quicker if I am sitting in traffic.My gauges have all only been straight in the middle. Thats why I
think the car is trying to tell me something. My Mechanic said that he checked and the car wasn't overheating and the fan was working. Another mechanic said it needed a fan and module replaced. Any ideas on what could be wrong? I'm afraid to drive it any distance or drive it until the gauge gets all the way to the "H". Any help would be appreciated.
Your engine temperature should run around 220* after running for a while (that should be about 3/4 of the gauge to toward the H). Have your mechanic check it and tell you what the operating temperature reads. Your battery gauge should read about 3/4 toward the right (equal to about 14 volts charging). After you start the car it should move back toward the center mark (equal to about 12 volts charging). Your oil gauge should move to the right (or high pressure side) when the engine is cold and then stay around the 1/2 way mark after it warms up. For your well being, I'd have your mechanic test the oil pressure with a gauge and let you know what it reads (both on a cold engine and a hot one). Best of luck and it's great that you listen to what your car is telling you.
I'm a big believer in Occam's Razor. If this were my car the first thing I would rule out is a slipping front accessory belt. Since it got wet with coolant the alternator may be belt slipping. This could cause low charging system voltage.
The low voltage will cause the temperature gauge to read high (falsely).
If planning to check yourself, measure the charging voltage. Look for evidence of belt slipping. Or if the belt is old and cracked, replace it.
If looking for a true "professional" mechanic maybe the one you have isn't thinking the symptoms all the way through.
Once the charging system has been confirmed to be in tip top shape, it's time to move to more complicated trouble shooting.
Was the T-stat replaced as part of the water pump job? I generally recommend replacing the T-stat after an overheating "event". Sometimes the wax inside the T-stat will be forced out after an overheating event. This will affect it's future operation.
The V6 is bad about trapping air inside the coolant jacket. IF the coolant filling procedure wasn't followed, there could be air trapped inside. This will block the flow of coolant. It will also affect the operation of the T-stat.
Thank you for your responses. I went to a retired mechanic. He said the alternator belt is fine. The other mechanic that put in the water pump did not replace the thermostat. Just now had alternator & battery checked. He said that was fine. We let the car run awhile & he said that fat hose was bulging out. But the fan goes on & off. He disconnected some skinny hose and put it in a jar of water. There were a few bubbles and a little green coolant. He is suggesting trying to replace the thermostat. When I drive back home and turned off my engine, the gauge for coolant stayed in the middle. When I start up the car, the gauge goes back down to the "c". Of course, as I start driving, the gauge goes to the right to the "a" of the word "normal" & then it will float back to the center & then go back up again. My car never did this before.
NOTE: it's NORMAL for the motor's temperature to vary over a level. But how do you KNOW if the temperature gauge is accurate? What has been done to measure the motor's actual temperature?
Your voltage gauge shows there's a problem of some description in the charging system.
The calibration of the temperature gauge is a calibrated voltage based upon the assumption that the alternator is charging to a net positive level. The low system voltage will make the temperature gauge read HIGH. This means the temp gauge is likely giving a false reading.
The battery and alternator may "test fine", but there's still a problem somewhere in the charging system. Perhaps a weak ground. I stand by my original recommendation. "Today's cars simply will not run right without a strong battery and charging system".
What’s the furthest that you’ve ever driven in a car that is solely relying on the battery? Anytime that I’ve had an alternator not charging the battery (bad charging system) I never made it very far.
When the motor is at operating temperature does the heater blow hot or not so hot? If the gauge says the motor is warm but the heater is not blowing hot air that usually means that there is air trapped in the system. Air in the coolant system will give a false gauge reading. The gauge will read sky high and yet the coolant is luke warm. If your upper radiator hose (big black hose connected to the radiator about waist high) is warm after the car has been running awhile the thermostat is opening and is “good.” If that same big black hose is hard and doesn’t squeeze so easy when the motor is warm then you have air in the system. Squeeze that hose prior to starting the motor. Then squeeze it again after it has been running awhile. If it has the same firmness as before and is hot, then there is likely no air in the system and the thermostat is good. If it isn’t very hot then the thermostat isn’t opening and needs to be replaced. If the hose is rock hard and hot then you have air in the system.
If your charging system is bad the you’re car wouldn’t have made it very far without dying.
I am taking the car in to get in to get the thermostat replaced tomorrow. Mechanic said it was an inexpensive part. I think I would feel more better/hopeful if only the 1 gauge was acting weird. But with the other 2 gauges also acting weird & the mechanic who put in the water pump saying that my car wasn't overheating. I'm afraid this won't fix the gauges & I will still be nervous to drive it. Well, this will be the 1st step. I will let you all know how it does. Thank you again for your suggestions.
It is a good first step that will give you peace of mind, also ask if the can pressure test the radiator cap while they have it. Improper pressure in the cooling system can lead to higher running temps as well
Hot or cool air coming out of the vents?
A thermostat from the parts store is between $10-$15. The mechanic will probably charge $20+ for the thermostat, and whatever an hour of labor costs plus however much they charge for coolant. So you’re probably looking at $120 or so.
When the temperature gauge is reading “hot” or around the “A” squeeze the hose that is circled in the pic. Can you squeeze it closed fairly easy or does it feel hard? Hard means there is air in the system. Hard/Bulging- air. When they change the thermostat they’ll need to “bleed” the system of air like they did or should have done when they replaced the water pump.
If your concern is that the temp gauge reads at the “A” in normal and it used to read around the “O,” a new thermostat probably isn’t going to fix it. When thermostats go bad they quit opening up and when that happens no coolant will get into the motor. So if it was stuck closed the temp gauge would be past th “L” in normal. But, if the temp gauge reads way high and the heater is blowing cold/cool air then there is air trapped more than likely. If the gauge is reading at the “A” or “L” and then air blowing out of the vents is hot then it could be a number of things. The radiator might be clogged or the electric fan isn’t coming on. When it reads at the “A” pop the hood and see if the fans are coming on. Also turn the heat on full blast and see if the temperature drops.
Squeeze that darn hose. That’ll tell you a lot.
Update: I had the thermostat replaced. No change at all. The mechanic said the old thermostat did have some rust on it. Before he replaced the thermostat, he said he put a thermometer in the radiator and it didn't register overheating. After driving tonight, turned off the car and the cold/hot gauge needle moved to the center & stayed there. When I
go to turn on the car in the morning, it will then move down to the left. The mechanic casually mentioned something about the cause might be leaky head gaskets??? Why would that affect my gauges?
Could be radiator. If top hose is hot and lower hose is cool radiator. Had same issue ran fine with cap loose. Afterward change thermostat to a 190. Do not get a fail safe
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