2003 LX Temp gauge flucuations/stays cold now
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2003 LX Temp gauge flucuations/stays cold now
Hello,
I have a 2003 Civic LX automatic with 205,000 miles. For 14 years my temp gauge sat with the needle steady just below 1/2 once it warmed up. About 6 months ago I was driving to the airport in stop and go traffic on a hot day with a/c on and it appeared to overheat, as the temperature rapidly climbed to the red. I pulled over and turned everything off, and there was no smoke or steam. Waited awhile and resumed the trip with a/c off. No further problems that day - temp back to steady at just below 1/2. Had mechanic friend check the coolant levels (normal), oil (normal), etc. No obvious signs of anything wrong. No overflow, no leaks under the car. Continued to run normally with the 'overheating' occuring 1x a month or so both with and without a/c on, until it started happening more frequently - 1x a week or so. Finally had the exhaust manifold gasket replaced as it was leaking, along with thermostat (honda brand), both fans with new motors and switches, and coolant flushed refilled and whatever you call getting the air out of the system. Car has run fine the entire time - not rough. Only code it ever threw was for an emissions leak, which went away after the exhaust manifold gasket was replaced.
Now, the car takes forever to come off the 'c' mark at the bottom of the temp gauge, and sometimes doesn't at all. Other times it will, extremely slowly, climb to almost 1/2, then rapidly fall to about 1/4 on the temp gauge, stay there for a while, then drop back down to the 'c' mark again. This is an old car, in good shape but high mileage and little value. I'm not sure if I should continue chasing the problem or just donate it and move on. One mechanic said it sounds like the water pump, but that was replaced on schedule and I don't think that is the issue. Hot air always works fine no matter what the gauge reads. The a/c just recently started acting up - works well when first turn the car on, but then eventually just blows outside air and the compressor doesn't kick on and off. Pressures are fine. I don't think this problem is related to the temp gauge flucuations. I don't care so much if the a/c works as long as the car is safe to drive with the wonky temperatures.
Any suggestions on what to look at next? Thanks!!
I have a 2003 Civic LX automatic with 205,000 miles. For 14 years my temp gauge sat with the needle steady just below 1/2 once it warmed up. About 6 months ago I was driving to the airport in stop and go traffic on a hot day with a/c on and it appeared to overheat, as the temperature rapidly climbed to the red. I pulled over and turned everything off, and there was no smoke or steam. Waited awhile and resumed the trip with a/c off. No further problems that day - temp back to steady at just below 1/2. Had mechanic friend check the coolant levels (normal), oil (normal), etc. No obvious signs of anything wrong. No overflow, no leaks under the car. Continued to run normally with the 'overheating' occuring 1x a month or so both with and without a/c on, until it started happening more frequently - 1x a week or so. Finally had the exhaust manifold gasket replaced as it was leaking, along with thermostat (honda brand), both fans with new motors and switches, and coolant flushed refilled and whatever you call getting the air out of the system. Car has run fine the entire time - not rough. Only code it ever threw was for an emissions leak, which went away after the exhaust manifold gasket was replaced.
Now, the car takes forever to come off the 'c' mark at the bottom of the temp gauge, and sometimes doesn't at all. Other times it will, extremely slowly, climb to almost 1/2, then rapidly fall to about 1/4 on the temp gauge, stay there for a while, then drop back down to the 'c' mark again. This is an old car, in good shape but high mileage and little value. I'm not sure if I should continue chasing the problem or just donate it and move on. One mechanic said it sounds like the water pump, but that was replaced on schedule and I don't think that is the issue. Hot air always works fine no matter what the gauge reads. The a/c just recently started acting up - works well when first turn the car on, but then eventually just blows outside air and the compressor doesn't kick on and off. Pressures are fine. I don't think this problem is related to the temp gauge flucuations. I don't care so much if the a/c works as long as the car is safe to drive with the wonky temperatures.
Any suggestions on what to look at next? Thanks!!
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Re: 2003 LX Temp gauge flucuations/stays cold now
Reads like maybe a flaky thermostat, but.....I'd want to see if the gauge is lying to you first.
And see if the temp sensor is lying to the computer.
Might have to do these checks while it's acting up though.
I'd plug in a scanner:
Code check, any code related to the ECT or thermostat performance?
See if the live ECT value (data list) reflects what the gauge needle is saying.....because the gauge is run using that temp sensor data from the PCM
Do the gauge cluster self test to see if the gauge sweeps correctly
You might be able to feel the top radiator hose and tell if it really is cool or screaming hot when the gauge says it is not.......if you can tell temperature by feel
AC...There's a zillion threads here. If it works fine at first then quits after the engine warms up, check for excess clutch plate wear/air gap (reshim or remove shim to correct clearance)
And see if the temp sensor is lying to the computer.
Might have to do these checks while it's acting up though.
I'd plug in a scanner:
Code check, any code related to the ECT or thermostat performance?
See if the live ECT value (data list) reflects what the gauge needle is saying.....because the gauge is run using that temp sensor data from the PCM
Do the gauge cluster self test to see if the gauge sweeps correctly
You might be able to feel the top radiator hose and tell if it really is cool or screaming hot when the gauge says it is not.......if you can tell temperature by feel
AC...There's a zillion threads here. If it works fine at first then quits after the engine warms up, check for excess clutch plate wear/air gap (reshim or remove shim to correct clearance)
