Diagnosing a blown head gasket - can I use a compression gauge? By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Service. To make reading the service manual easier, download the file to your computer. A few months ago the temperature gauge started reading hot. There is nothing else feeding into that dash gauge right? This sends a signal directly to the dashboard gauge. Or just get a new one.. Temp sender unit is faulty: Remove the sender unit wire and earth it against the bodywork and the gauge should go straight up to hot. Another reason the temperature gauge could read cold is if the thermostat in the vehicle stays open. Hi, Have you checked the coolant level in the coolant reservoir? Adequate DMMs are available from larger hardware stores for about $15-20. but the engine is so hot you can't touch it while just sittin there and idling and there is smoke coming out from around the exhaust manifold, which it never did before. A broken temperature gauge can lead to expensive vehicle repairs. It should have said pcm. So check that measurement again. If you measure around this value (or definitely not near 140 Ohms) with a cold engine then the unit is faulty and needs to be replaced. How it works is. Both fans will turn on when I turn the AC on. Your call if it worth going to a dealer. sender, could be wiring between the sender and the gauge, could be the gauge. Question: My temperature gauge, in the car, reads normal, and the motor doesn't over heat. Keep adding coolant mix to keep all radiator fins covered - just below the filler neck. A quick test is to disconnect the lead from the sending unit, turn on the ignition and observe the temp. The resistance of the sensor between the body of the sensor and the sensor connector tag should be ~140 Ohm when cold. The exact “normal” spot can vary from vehicle to vehicle, but as long as it’s more or less in the center, all is well. What is this stake in my yard and can I remove it? Are more than doubly diminished/augmented intervals possibly ever used? when starting the car the temp. Since you are experiencing no overheating problems the most likely cause is that the engine coolant temperature sending unit is faulty. See p.10-19 for the troubleshooting section regarding your problem with the radiator fans. If there are small bubbles bursting, it isn't bled yet. However, when replacing with new sensor, gauge on dash goes to full red at startup, very surprised by this. Thank you so much!!! This sensor is nothing more than a thermistor -- a variable resistor that changes resistance with temperature changes. Looking for a little help with a temp gauge that seems to be too hot. If you measure around this value (or definitely not near 140 Ohms) with a cold engine then the unit is faulty and needs to be replaced. The most common problem when it comes to a faulty … Making statements based on opinion; back them up with references or personal experience. If you don’t know how to use a DMM get one that comes with a good user guide (some are woeful) so that it will be easier for you to understand and use. so I'm assuming that the thermostat is working fine. I'll take it out tomorrow for up close examination for burs. Especially if the sensor is in the very top of a housing, where air may accumulate. I have a 98 accord and let run for twenty minutes, battery light, engine light, and all doors lights said they were open, car never warmed up, turned off and turned back on and lights turned off and after diving 5 miles or so car started to warm up. However, if the gauge approaches the higher (hot) end of the scale under normal driving conditions, it usually points to problems with the cooling system. It quit reading all together so I bought a brand new gauge temp sensor and it reads wide open all the time. It's an electrical concern. Does crank length effect the number of gears a bicycle needs? Wondering what else can check for, seems this coolant temp sensor is at the end of the line of things. @transmission, Wrong there are a total of three sensors that can effect your guage cluster 1 on the thermostat housing two on the end of the head and 1 underneath the head on the back of the engine all the sensors are in direct contact with the ECM so if it pegs at cold then first I would check the one on the thermostat housing first it may be giving a bad ground to the sending. Do Jehovah Witnesses believe it is immoral to pay for blood transfusions through taxation? The readings are as I posted in the Chosen solution. The temp gauge goes to overheat. Stack Exchange network consists of 176 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. upon cold start gauge on dash goes to full red in 1 or 2 seconds. Thank you again.. Most gauges in today's cars run on an … The temperature gauge reading starts out as a reference voltage that is sent to the coolant temperature sensor. If the resistance was 570 Ohms it would read 1 which represents that it is above the chosen scale maximum reading, if the meter was on the 200 Ohm scale but .570 on the meter if it was on the 2K Ohm and 0.57 on the 20 K Ohm scale. Another reason the temperature gauge could read cold is if … If so, you still have to track down the problem, but you know what you are looking for! It kept overheating and I changed EVERYTHING. Either way, the best thing to do in this case is to have your car checked. Sorry...we did that to...I just looked at the receipt....any chance it's the pump? Reasons the Temperature Gauge Reads Cold On most vehicles, the temperature gauge reads cold until the engine has run for a few minutes. I have a 99 Buick century it had overheating problems so I replaced the water pump and thermostat flushed out the radiator and put new coolant. The vast majority of car temperature gauge systems feature a numberless panel with a needle that swings from C to H. It’s a mistake, however, to think that this type of gauge is giving you an accurate readout of your car’s motor temp. A quick test is to disconnect the lead from the sending unit, turn on the ignition and observe the temp. (It should also show 1 when the meter is set to Ohms and the test leads aren't connected to anything i.e. Terms — Can I run 300 ft of cat6 cable, with male connectors on each end, under house to other side? A small shard of metal is all that it takes ;-). When the bubbles stop, cap the radiator BEFORE you turn the vehicle off. I'll bring my ohm meter to napa tomorrow too. 140 Ohm (or more) when the engine is both cold and hot then the sensor is faulty and needs to be replaced. I'm a single gal who doesn't want to be taken advantage of...any ideas? What is a productive, efficient Scrum team? gauge says red hot. I’m kind of at a loss at the moment. James, Hey i broke my temperature gauge when i was taken out my heater house so i took off the distributor cap so I can get to the sensor and went to replace it and I guess the guys at the store didn't know what I was talking about so I'm about to censor to him and he gave me one but it didn't look right I put it on the car anyway now my car doesn't start what's the problem I'm just a girl and I'm working on on my own and I'm trying to learn it and I don't want to &&^& it up please somebody help me. (you can do this out of the engine). Motor Vehicle Maintenance & Repair Stack Exchange is a question and answer site for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles. What can this be?? How I can ensure that a link sent via email is opened only via user clicks from a mail client and not by bots? Whereas if it was 57 Ohms it would show 57.0 on the 200 Ohm scale and .057 on the 2 K Ohm and 0.05 (possibly varying to 0.06) on the 20 K Ohm scale. temp gauge is on cold, but the A/C off due to high engine temp, yet not hot when I check engine. Signal can go to the pm then to the gauge, it may go to a body module then to the gauge. If I remove the wire from the sending unit, the gauge should stay on cold. Ohms is way too high according to what I 've been driving the car, reads normal.... Really erratic effects on the 2K scale is more accurate than 0.57, which has resulted in the very of. Sensor ( ECT ) says 've found out A4 with a cold surface, and not by bots a into... 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