Temp sensors bad?

I am having the exact same issue that you describe with my Barchetta.
I also own an 04 575 Maranello and that car runs cool and it does not heat up like the 550.
I can actually feel the cabin area getting warmer when I drive my 550 and am stopped at the lights at times.
It is a little un nerving to be honest.

I would like to add I drove the car this past Saturday and the temperature was only 70 degrees fairenheit, and my gauge was going up when stopped at a light. Like yourself, it does not happen at every light

It will be interesting to read if anyone else has had issues like this, or even overheating issues.

 

If that does not work read my post (not a bad thing to do anyway)
http://www.ferrarichat.com/forum/showthread.php?t=299091
it's perfect now.
Take Care,

Bill

 

Bleeder hoses!

A 550 that has the gauge go past 190 has a problem.

 

I think the overflow is not what Dave means, I think he means the hose between radiator and expansion tank. That thin hose can gum up completely. Also make sure to check and open up the inlet pipes to the expansion tank and radiator. They're tiny!
Get the original hose, it's not expensive. And it's got those cute marks to remember where to put the hose clamps...

 

Nothing in factory literature for late model Ferraris tells you to change coolant every 2-3 years. If this has not been done, make sure you do it because the anti-corrosion additives wear out. If you change any hoses, make sure you use 575M or Scuderia Rampante hoses, which are silicone. Dave's hoses are the best you can buy.

Taz
Terry Phillips

 

And not worth the money being charged for it.

The OEM hose fails internally and can look perfectly good on the outside while being completely collapsed on the inside.

One bleeder from the Valley and one from the radiator, both serve an important function.

 

Dave thanks, I changed the radiator to expansion tank already, but I´ll check the other one tomorrow if I have it on my car (456), now you got me scared...

So the original is crap. I should get silicon ones?

 

to adequately get to those hose the pleunum needs to come off unless you got baby hands, long arms and can bend your back 120 degrees. So you may as well pull the tsensors and put them in a pot of boiling water with an ohmeter on them and you can see if they are working too.

 

Ditto FBB.

As one that makes special Silicone hose because I was completely fed up with what was available, Silicone or Rubber.... yes! Not all silicone hose is created equal, some is worse than rubber!

 

Christopher,

Try cycling the temperature control on the HVAC a few times, slowly, full hot and cold with the compressor on.

Barry

 

Christopher,

From what you're describing, the water temperature sensors might indeed be the problem. You now have a new thermostat and you've drained, flushed and refilled the coolant properly. Your left and right radiator fan relays appear to be working properly as well.

Please keep us posted.

Barry

 

Christopher,

If it's the temperature sensor(s), then indeed your 550 would not be overheating but the water temperature gauge would read intermittently high as your experiencing when your car is stopped at a light or in traffic. Once underway, you would get more normal readings.

Does your water temperature warning light come on when you get these high gauge readings?

Your relays are probably OK if the fans are kicking in. High water temperature gauge readings would occur if the fans are running with a faulty temperature sensor. What makes you think it's the left sensor?

Barry

 

Christopher,

I reacquainted myself with the section in the WSM, Cooling System pp. B64-68. In addition, I inquired at Classic Coach where I have my 550 serviced and failing water temperature sensor(s) is a very real possibility with the symptoms your car exhibits. It's probably best to replace both sensors considering the age of the car.

Barry

 

Christopher,

I think the temperature swings on the 550 are due to the hysteresis of the sensors (fans come on a couple of mm past the middle line, and go off a couple of mm before) and to the huge thermal inertia of the 20 liters of coolant.

By observing mine I have noticed that if the AC compressor is running when I stop at a traffic light, the temperature doesn't rise much beyond the middle line, because at least on of the fans is running.
This is also true when I stop and both fans are already running.

However, if the temperature is below the middle line and no fans are running, when I stop at a light the needle will rise beyond the middle line, both fans will come on, but the temperature will still rise for 20 seconds or so, until the cool water from the radiator actually begins to cool the engine.
Under normal conditions the needle never goes beyond 3mm over the middle line.

However, what you are reporting - 240F - is too high and Ferrari says you should never exceed it. At that temperature the additives in the coolant decay very quickly.
This summer I was in a traffic jam in 100F outside temperature in France, and the needle nearly reached that 3/4 white line, meaning the coolant was at around 230F.
So I decided to park the car and just wait for the traffic to clear.

If you're reaching 240 despite both fans running, you might consider changing the coolant, it's probably so decayed that it's not doing its job properly.

Stefano

 

The two plenum gaskets (to avoid vacuum leaks in the near future), the small rubber hose under the big one, and the one going to the expansion tank.

Stefano