I’ve got a 2002 Ford Taurus with over 200K miles on it, and as is bound to happen with a car with that many miles on it, it has started to have a few parts needing to be replaced. Things don’t fit right anymore, and fittings wear out. Well, my Engine light came on a long time ago, and I took it to have the code read. It actually had two: ECT low and ECT high. The guy at the shop I took it to was stumped, and said that they’d look at it if I wanted, but didn’t want to commit to any sort of solution right away. It’s had a few problems with its cooling system already, and I happen to know that it also has a slow leak somewhere. After about 3 or 4 months, all of its fluid will have leaked out, and I have to fill it back up. I don’t really think these are the same problem, though. Any thoughts?
Are you sure it is leaking? Could it be going into the engine? Think head gasket. It should not be loosing fluid.
BTW it is not a good idea to leave that engine light on. I don’t know your car so I can’t suggest a solution, but I would want to act of that light. The problem is you will not have anyway of knowing if something more urgent and serious happens and you could do some serious damage since your car’s computer can’t talk to you.
Yes, the ECT sensor (engine coolant temp) can be affected by low coolant. It could also be that the ECT itself is bad.
The ECT can also be easily checked with an ohmmeter. If it’s bad enough to set a code then it’s bad enough to test. Odds are it’s low coolant though.
Since the car has a known leak you should not be going 3-4 months before inspecting the coolant level AFTER it’s all leaked out. This is a roasted engine waiting to happen.
A stuck or sticking thermostat might be the only problem. Does this car have a temp gauge? If so, does it stay in the ‘normal’ position mostly, or stay low or go high?
It always stays in normal range, and I don’t let it run dry or anything. As soon as I notice it’s gotten low, I add more. I’ve seen no ill effects from doing this yet, but I’d like to have it fixed. I just want to know what it is I need to have fixed. I mean, I’m not sure really if it’s leaking or boiling off. If it’s getting too hot in there, it might be that. I have on a rare occasion noticed a smell of antifreeze when I park the car and get out. It makes sense that it might be the thermostat getting stuck. I dunno.
Are there any coolant stains (chronic ones) on top of and around the coolant resevoir?
Maybe a pressure cap acting up and allowing coolant to weep out and burn off?
Other than that, about the only way of knowing for sure would be to have a cooling system pressure test performed to determine if there is a leak in the cooling system and if not, then it could be the cap.
Or replace the cap and hope.