The temperature gauge on your car is a fairly basic tool though it is an extremely important one and it can be very frustrating when your temperature gauge is not working. The technology has changed little from even the oldest models of cars and essentially its job is to do exactly what it says, it tracks the temperature of your engine.
If your temperature gauge is not working, there are some things you corso base teorico pratico di indicizzazione per soggetto. 2 modulo to know. The first thing you always need to look at with a strange reading on your temperature gauge is giving a strange reading is the actual temperature of your engine. Always rule that out first before focusing on the gauge itself.
If you know the engine temperature is not an issue, you probably have to deal with one of these problems. But there are some things you can do yourself.
Without a proper diagnostic it can be difficult for the average car owner to know definitively if the problem with your temperature gauge is the gauge itself or the engine overheating.
There are a few tricks to help you narrow it down on your own without paying money to a mechanic, however. Checking your temperature sending unit is a good first step in determining if and why your temperature gauge is not working.
The sending unit is not that hard to gain access to than the gauge itself and, on average, is more likely to fail.
How your temperature sending unit works depends on your make and model. Some models have two units, for instance. Older cars will have the unit connected directly to the gauge while most cars from the mids onward have the electronic control unit as the intermediary between the two. There are a number of sites online like this one that offer a wide range of manuals based on make, model, and year. Testing is fairly simple. A faulty thermostat will have a similar cost in terms of parts and labor as well.
Some might argue that if it is the gauge itself not working and the actual engine is running fine, then there is no need to repair the gauge, or at least no need to prioritize it. This line of thinking could be very dangerous in the long run for your safety and the life of your vehicle.
Think of it like a faulty smoke detector in your house. Until there is a fire. This is the same as with your temperature gauge. You have no way of knowing if your engine starts running hot if the gauge is not working. The longer it does run hot, the greater potential for more damage and high repair costs down the road. For a relatively cheap repair cost, you could save yourself a massive bill and a lot of time and aggravation down the road.
If your temperature gauge is not working, you really should get it fixed. Why Us? If this is the case your sensor will be reading the coolant temperature incorrectly and sending the wrong signal to the gauge.
A malfunctioning circuit in the temperature gauge Faulty wiring is a potential culprit, and it can be traced to several spots in the whole system. You can have broken wires leading from the gauge itself to the sensor or wires from the sensor to the engine control unit.
If not, then let your mechanic handle it. A contaminated coolant system will cause inconsistent readings and requires a full bleed of the system to repair. If you have air or something else in the lines, your gauge will probably be reading up and down as it passes through or stay cold if air bubbles get stuck on the sensor itself.I have a Nissan Sentra.
In Nov. Right after that, I had no heat and the temperature gauge would go up to hot but then come right back down. Brought it back to mechanic, changed thermostat and both things ok only part way home. Started riding with coworker only driving to her house 7 miles away and still temperature gauge up and down, stopped driving completely in Feb. Just brought it to dealer who replaced thermostat and worked fine all the way home and then started all over again the next day.
Seems to happen faster at higher speed but will eventually do it in any driving conditions. Today service engine soon light came on. Obviously not thermostat problem. Could it be water pump? Any help would be greatly appreciated. Have you personally checked the coolant level?
Not just the overflow bottle but the radiator also. You have air in the cooling system.
On some cars this involves removing a plug in the block until coolant flows out. How does the coolant look? Another cause for air in the cooling system can be a head gasket issue, combustion gasses getting into the cooling system. Shops can test the coolant for this but you said that a pressure check was done and ok.
It is still possible that a head gasket leak into the coolant may not be found by a cooling system pressure check but if done carefully it will usually tell. The check engine light makes me suspicious but we need the code. A lot of chain autoparts stores will pull the code for you for free AutoZone, Advance Auto etc. Get the code read and report back. I agree. This sounds like an air pocket in the cooling system. Have you checked the coolant level in the radiator? If not, you need to do so right away.
As with any electrical troubleshooting it is best to check all wiring connections are clean, tight and free of corrosion. The first place to start is at the temperature-sending unit. Remove the wire from the temperature-sending unit located on the engine typically a dark green wire. Then connect the wire to a good ground. You can do this by using a jumper wire. If the needle does not move, remove the same dark green wire from back of the gauge and connect a jumper from the terminal on the back of the gauge to a good ground.
If it does not move, connect a test light by grounding one end to a good known ground and the other end to positive side of the gauge typically a pink wire.
It only takes a minute to sign up. I've noticed on my 94 Integra bought used about 2 weeks ago that the thermostat is often below cold, sometimes above cold but never up to the center mark. Today I was boiling inside my car as it was a very hot day and my thermostat was below cold for the engine.
3 Essential Things to Know About Your Car’s Temperature Gauge
Any ideas whats up? From searching it seems like the thermostat might be broken but I don't understand why sometimes it goes above cold. Not sure if this is the same on the Integra, but on my SEAT Leon I have the same issue, and the cause I believe is that the thermostat is stuck open - this is either due to a failed temperature sender unit so the thermostat never gets the signal to close or the thermostat itself needs replacing - that'd be the first places I'd look.
The coolant system is designed to keep the engine at a near constant temperature. If the temp is too cold it affects fuel ecconomy and performance. If it is too hot engine parts overheat and get damaged. The thermostat does this by opening and allowing hot coolant into the radiator to be cooled. When the coolant temp is low it closes and allows the engine to warm to the designed temperature.
The are three most likely causes. A defective thermostat that stays open. This allows the coolant to flow thru the radiator and actually overcools the engine. It could also be a defective gauge ot sensor.
The other cause is a defective coolant fan relay. If the radiator fan runs constantly it can also overcool the engine. As others state, it could be related to your thermostat. Depending on the operating temperature range you could test it in water and check at which the thermostat will open. Another issue that you might want to check is how accurate your gauge really is. You might want to install an aux. My gauge on my Land Cruiser is more an indicator than anything else.
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Q: Why is my temperature gauge going up and down?
Car temperature displaying below Cold or just above Cold always? Ask Question. Asked 7 years, 9 months ago. Active 5 years, 3 months ago. Viewed k times. Hmm okay.
Sir, I have the same situation with my civic EG, it has a JDM B16a transplant, whenever the key is turned to ignition, it turns on the radiator fan continuously, it is no longer connected to the thermostat and the relay, we usually do that here in the Philippines.
Active Oldest Votes. Thermostat sticking open is a very common failure. OP, what's your climate like? Where I live, it's hot enough that even with the thermostat wide open the engine won't stay at CMy thermostat starts on cold and when i get in and drive it goes from low to almost hot.
Do I need to change the thermostat, I add water and coolant but it does the same thing. CaptPKelly answered 5 years ago. If this is gradual and it get's hot while sitting in traffic, cooling when moving, or goes very hot after coming off the Interstate, then it's a "stuck open" or possibly missing if previously owned thermostat.
Replace it and be happy it wasn't stuck closed. If the change is rather quick and jumps around the gauge for no apparent reason then it may be a faulty temperature sensor. If this is the case, replace it because it will put undue stress on an electrical cooling fan with frequent starting and stopping. Most likely a corroded and stuck-open thermostat.
John answered 5 years ago. My guess would be a temp sensor going bad. Have someone with a temperature gauge gun shoot the car and see if there are any hot spots in the area of the thermostat.
The thermostat is cheap to replace, time is the only thing. It will require draining the coolant from the radiator, the removing the thermostat housing, usually two bolts.
Some thermostats can be put in upside down, so pay attention to the arrows on the thermostat. The water should flow from the engine towards the radiator. The temp sensor I think is in the rear passenger side of the engine on top. If none of these work, see if anyone can hook up a second gauge to make sure the one on the dash is working correctly.
Pam answered 4 years ago. My thermostat is going up when I'm going then when I stop it goes down what could be the problem I done replace the temp. CaptPKelly answered 4 years ago. Pam, your problem seems similar to the original question. If the thermostat is working as it should you should not see moving water for a few minutes. If water begins circulating immediately inside the radiator then the thermostat needs to be replaced. There are a few other major problems that can make the engine temperature fluctuate as you describe like a blown head gasket or a cracked head.
If you are sure the thermostat is working properly, and if you are not doing the work yourself, have a mechanic check your radiator for exhaust gasses with a "sniffer".
You can also look for white smoke or steam in your exhaust. If either or both of these check positive then I'm afraid your problem is a little more expensive than a bad thermostat. Don't let anyone tell you that unless you have water in your oil you do not have a cracked head or blown head gasket. Neither have to necessarily allow water to flow into the oil, but can allow exhaust to pressurize the cooling system causing it to circulate improperly.
Dear alli need help herei am having the following problem : Temperature gauge goes up and down from 90 tocompletely randomly sometimes it doesn't happen and sometimes it does, no difference if i driveor stand at a traffic lightor drive smooth or hit the road hard.
My car is an aud s6 model 5. Than problem occured after i had a blown gasket due to a malfunction of my thermostat couple of month ago. Gasket has been replaced at that time but after hundred km without any issuei am facing this constant problem of the temperature gauge going crazy and for whatever reason it comes from 90 steady up to in about 30 to 40 seconds and then it comes back down while im still driving, and then all the cycle againup and down up and downsometimes more than and soemtimes less.
The engine is not over hittingcoolant is not boiling ,cooling system pipes are not hard and can be pressed bare hands.The dashboard gauges in your car tell a complex story about everything from your current rate of speed to the state and health of your engine, and even whether or not things like your headlights are switched on.
Different vehicles have different gauges, and some instrument panels are much more complicated than others. When one gauge stops working, the problem may be in the gauge itself or a bad sensor, while all the gauges cutting out at the same time often indicates a blown fuse or a defective instrument cluster.
The most common causes of the gauges in a car not working can be broken down into three scenarios:. There are a lot of different types of instrument cluster designs and configurations, but when all of the gauges in a car stop working at once, the problem is usually either a fuse or wiring problem.
The first step in diagnosing this type of issue is to identify the fuse associated with the instrument cluster or gauges. The fuse should have power on both sides when the ignition key is turned to the on position. If the fuse is good, the next thing you or your mechanic will want to do is to check for power at the individual gauges.
This usually requires removing the instrument cluster, which can be quite difficult and time-consuming in some vehicles.
How to Troubleshoot a Car Engine Temperature Gauge
At a bare minimum, you will probably have to remove some trim pieces and unscrew the cluster to pull it free. The difficulty level is usually on par with installing a new car radioso if you're comfortable with that job, you can probably handle this one. You may be able to check the ground by looking up under the dash with a flashlight, but you will have to actually remove the instrument cluster in many cases.
When the gauges seem to move erratically, or they are pegged at the highest possible reading, the problem is usually a bad component like an instrument voltage regulator or a bad ground. Erratic gauges, or gauges that seem to read uniformly low, are usually caused by a bad instrument voltage regulator. In some cases, you may be able to remove the regulator, clean the connector terminals, and reinstall it. Gauges that all read full all the time are usually caused by a loose or bad ground.
In some cases, you may find that the entire instrument cluster is bad. Early electronic instrument clusters had digital readouts much like an LCD alarm clock, while the modern equivalent often simulates analog gauges in a much more sophisticated way. In either case, diagnosing and repairing or reconditioning this type of instrument cluster is outside the realm of the typical do-it-yourselfer, unless you want to just replace the entire thing and hope for the best.
When a single gauge stops working, the problem is either in the gauge, the wiring, or the sending unit.Temperature gauge not working?
If you are comfortable locating and removing sending units and sensors, you can diagnose this type of problem yourself. Using your coolant temperature gauge as an example, the diagnostic procedure involves locating and disconnecting the sending unit.
With the ignition on, the gauge should register cold.It is an important dial that is located on the dashboard of your vehicle. If the temperature gauge reads high, it could mean your engine is overheating. Another reason your reading might be high is you could be losing coolant. A small leak or evaporation may cause your radiator to slowly lose coolant.
A third reason your temperature gauge reads high could be because the thermostat is broken. If this is the case, you may need a coolant temperature switch replacement. The last reason the temperature gauge could read high is because of a water pump, or water pump gasket failure.
If the water pump is malfunctioning, it may need to be replaced by a professional. On most vehicles, the temperature gauge reads cold until the engine has run for a few minutes.
If the temperature gauge still reads cold after the engine has warmed up, the gauge may simply be broken. Another reason the temperature gauge could read cold is if the thermostat in the vehicle stays open. With the thermostat stuck openthe engine can be overcooled, causing a low temperature reading. If this is the case, the thermostat may need to be replaced. If your temperature gauge is reading high, it means your car is overheating. This is a very serious matter and you should never drive an overheating car.
If your car starts to overheat, shut off the air conditioner and open the windows immediately. If this does not reduce the overheating, turn on the heater as high as it can go. If this still doesn't work, pull over on the side of the road, turn off the engine, open the hood carefully, and wait until the vehicle cools down.
Never open the radiator cap while the engine is hot — coolant can spray and burn you. Once the vehicle has cooled, take the car to a mechanic right away so they can diagnose the problem. Cars are especially susceptible to overheating in hot climates, like what's common in cities like Los AngelesPhoenixLas Vegasor Atlanta.
Contact YourMechanic and have your car inspected for overheating if it reads too high, as this can cause serious problems. The most popular service booked by readers of this article is Car is overheating Inspection. Our certified mobile mechanics make house calls in over 2, U. Fast, free online quotes for your car repair. Schedule Car is overheating Inspection.
Service Area. Average rating from 1, customers who received a Car is overheating Inspection. Reasons the Temperature Gauge Reads High If the temperature gauge reads high, it could mean your engine is overheating. Reasons the Temperature Gauge Reads Cold On most vehicles, the temperature gauge reads cold until the engine has run for a few minutes.
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