So, it's the first fairly warm day of the year - 88 degrees Fahrenheit outside right now (31 C for those of you in the rest of the world!), and I haven't really had the car all too long. I bought it in the middle of the winter, and don't really have much of a baseline for how warm it should be running on a hot day.

However, I was quite worried when I saw it spiking well above where it had been running in the past...

Photo below of the temp it seems to be running at now (bouncing around a little, but well above 80C for the most part)...



My question to all of the experts out there: Is this normal for a hot day with the aircon running? Do I need to be worried about a water pump in my near future?

Thanks in advance everyone!

Seems normal to me in hot temperatures especially if the car is just sitting. I wouldn't worry about it.

Looks like a bit on the high/hot side.

Mine sits just above 80ish (81/82). But when at a full stop for a few mins or so or sitting in traffic then that's about where it should be.

That kinda high, even with the supercharger on a 70+ summer day my temp hoover just about alittle above the 80C mark in traffic. Try flushing your coolant system.

Yeah, this isn't sitting in traffic. I noticed this right after I got off the freeway. Was at a stoplight for about 2 mins, and started driving again - and it hovered around that point until I shut down the car later in the day...

I'm guessing it's time to flush the antifreeze, per Peter's suggestion...

Try that and see if it works. Let us know.

+1 If I were you would only use MB coolant. Some will say otherwise. Also while the car was running hot, did you hear your aux fans kicking in? On my car when it runs hot you can hear the aux fans kicking in high gear to cool her down. (standing in front of the car)

Armani

Make sure it G-05, they are the same as MB antifreeze/coolant but cost less and you can buy them at local auto parts store.

That OEM T-stat assy has a 87*C . It will start to open somewhere near that Temp. It would not be unusual to see 100*C at low speeds & Around town in traffic Driving. A good radiator & cooling system flush could not hurt considering the age. Cheers _PTEngineering

Exelent 1+! here in my country the temp in owr cars round 87° - 95° degrees. if you read the owners manual you can check the temp can reach the 100° in hot seasons by a normal operation, the instrument cluster reads 100° in white lines right? red line = BAD = STOP, but white lines are normal operation variating the external temps

Fabio Danie l

Check your fan clutch. Mine was out but you couldn't tell until my friend decided to bounce his fingers across the blades until the fan slowed down and he could hold it with no force. He was doing this at the engine temp you describe. But using my A/C unit, I was able to read out the engine temp at 110C even though the needle indicated it was below the 100C mark.

To check when your engine is hot, if you rev the engine, the clutch should be grabbing and the fan should spool up a bit you WILL notice a bunch of air being pushed by the fan. But not through the entire rev range of the motor. I'd say maybe up till 3k rpm max, then the fan wont go any faster.

Another way to check ur fan is when the engine is cold. See if you can touch the back side of the fan clutch where it faces the engine block. If you feel a bunch of oily grime, the oil has completely leaked out of your fan clutch and you either need to refill it or buy a new one.

I did a coolant flush, but that only helped like 5C at most.

PS after the fan clutch job, my car still gets the needle to sit at that spot if I'm not moving in traffic for more than 10 min and its 80F outside.

Did the flush... and it did the trick. Car seems a lot happier now! Running a bit cooler, but still does hit that spot if I'm not moving for a while.

Used the Orange MB coolant fluid. The car had the blue MB fluid in it before...

That's normal.