had an indication all might not be well a couple of weeks ago, not a hot day, when I pulled into a parking lot and after idling for a minute or so the 1st level warning “engine temperature high, reduce speed” came on… first time I had ever seen the temperature gauge on the TFT DIM move above the line… shut the engine down and went about my business… came back about an hour or so later, checked the coolant level, which was just right on minimum, down a little bit from the last time I had looked at it… drove the short journey home with one eye glued to the temperature gauge , nothing happened so I topped it off with a dash of the 50/50 mix I had left over after changing my coolant some months ago. Nothing happened next day either, but as a precaution I dug out my Bluetooth OBD thing and hooked it up to my phone to keep an eye on things…. all was fine every time I fired it up until yesterday, moving slowly in traffic I did notice the temp gauge creeping up…. It went back down again every time I got moving again, and got to where I was going where it had over an hour to cool down before I went home. Fired up the Bluetooth OBD and monitored… DIM gauge hits normal at about 150 on the Bluetooth readout, and that seems to level off at about 190 for me most of the time… First traffic light I noticd it climbing up above 200, quickly dropped back down once I started moving again… next light was a long one… temp got to 230 but the dim was still on the line, then got to 240 at which point the needle moved up… at 250 the reduce speed warning comes on but at that point I started moving – at 40mph on enough of a downgrade that I was coasting it got back under 200 quite quickly, but as soon as I got stuck in traffic it shot up again very quickly and the “stop safely“ message came up so I parked immediately and got my daughter to come and pick me up.
drove it the 7 miles home gently in the relative cool with no traffic early this morning… didn’t get to 180…
Examined the engine bay, tank is still midway between min/max, no signs of leaks, no puddles were under the car this morning or in the area of any of my normal parking spots… Serpentine belt seems taut, spinning, and the water pump is turning as far as I can see… only thing that strikes me as odd is only one of the two radiator fans is spinning… loaded up Vida which didn’t tell me anything… I did activate the cooling fan with Vida – there seems to be just the one setting – and only one of the fans Was turning even with that… could that be the issue, maybe… are both fans supposed to operate at the same time… Given that the problem is happening when I’m stopped or moving slowly it seems logical that this could be it…
obviously the car is getting old in terms of years and mileage so there are a bunch of other possibilities… thermostat & water pump are both original as far as I know, certainly not replaced in the 27 months/100,000 miles I’ve had the car… neither are expensive and I’d be willing to replace both in a heartbeat if only they were a little easier to get at. Any way to determine whether either of these are functioning while still in the car?