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**UPDATE**
The dealer called me back saying the temp gauge shot past 90c while they took it from the parking upstairs down into the service bay, the drive was short so the dealer said it was odd for the car to overheat this quick.
They have found an exhaust gas temperature sensor bank 1 fault code and I have ordered a new egt sensor.
The dealer said that the egt sensor can make the car think that its overheating.
Hope this fixes the issue.
Any doubts about this, please guys let me know.
IIRC, it's usually just the little circuit board in the EGT sensor loom that fails, not the sensor itself. You can get replacement circuit boards from a guy in Eastern Europe (Poland, maybe?).
IIRC, it's usually just the little circuit board in the EGT sensor loom that fails, not the sensor itself. You can get replacement circuit boards from a guy in Eastern Europe (Poland, maybe?).
I ordered the whole thing because usually the sensor melts into the manifold.
Ordered it for $79
$79 sounds like a Chinese knock-off. I'm not sure about the EGT sensors, but I know the knock-off O2 sensors are very prone to throwing codes and setting the check-engine-light.
Just to be clear: I have no experience with either the Chinese EGT sensors nor the Polish boards; just Chinese vs Bosch O2 sensors.
Oh, do you have an inductance heater? If not, you're very likely to damage the bung when getting the old sensor out. Plus you'll find them terribly useful for other stuff (an inductance heater and a borescope rank at the top of my list for "why didn't I get one earlier?")
Hello @Sal-Man,
There's only one problem with your update, a failed or failing EGT sensor does not actually move the temperature gauge to past 90°c, or at all, the failing EGT sensor will give a false "OVERHEATING" warning in the DIS as shown below, you can see the warning along with the normal temperature, not once in my years on here have I ever seen the EGT sensor move the temperature gauge.
Being that you have a 2011, I understand a single fan, has the fan been inspected for any damage, or proper working order, such as it's variable speeds, does the fan increase in speed at times, or AC on ?
Next, has anybody checked your thermostat, as your 2011 should have the thermostat with 87°c / 188°f opening temperature, which is the same thermostat in my 2011 Supersports engine, it's sits right at 202°f / 94.44°c constantly, you could have a faulty thermostat leading to reduced flow at times, therefore running hotter.
Remember, your 2011 thermostat is not electric like the early years, they had a 100°c / 212°f opening temperature, but used a electric heating element to manipulate the thermostat to open before the coolant actually reached that temperature.
Hello @Sal-Man,
There's only one problem with your update, a failed or failing EGT sensor does not actually move the temperature gauge to past 90°c, or at all, the failing EGT sensor will give a false "OVERHEATING" warning in the DIS as shown below, you can see the warning along with the normal temperature, not once in my years on here have I ever seen the EGT sensor move the temperature gauge.
Being that you have a 2014, I understand a single fan, has the fan been inspected for any damage, or proper working order, such as it's variable speeds, does the fan increase in speed at times, or AC on ?
Next, has anybody checked your thermostat, as your 2014 should have the thermostat with 87°c / 188°f opening temperature, which is the same thermostat in my 2011 Supersports engine, it's sits right at 202°f / 94.44°c constantly, you could have a faulty thermostat leading to reduced flow at times, therefore running hotter.
Remember, your 2014 thermostat is not electric like the early years, they had a 100°c / 212°f opening temperature, but used a electric heating element to manipulate the thermostat to open before the coolant actually reached that temperature.
My car is a 2011 and has a single fan setup like the 2007 and later models. My thermostat should normally open at 105c but currently what I am seeing is intermittently the gauge passes the 90c mark which is buffered from 75c-116c then it goes to the 120c ish side for a couple of seconds 3-4s slowly then quickly jumps back to the normal 90c area after the fan kicks in.
The fan according to the dealer are working in all 3 speed properly.
This happens some drives and sometimes doesn't happen.
The dealer suggested I would change the egt as this can be the root of the issue but I am not convinced 100% as this gauge dropping thing happens intermittently.
Can this electric thermostat be recalibrated?
Or does my 2011 continental flying spur speed use an electric thermostat at all?
Hello @Sal-Man ,
My mistake, I meant to write 2011 for your vehicle.
Your 2011 does not use any electrical thermostat, that stopped in 07-08.
As to your comment of your thermostat opening at 105°c, I believe that would be incorrect, as the 2008 and up used the non electric 87°c thermostat, not the 100°c electric one that the previous years used, and the 105°c electric thermostat was used in the 05-10 Audi A8L W12, I have one in my A8L W12, so, has anyone ever replaced your thermostat, where did you get the 105°c opening information from ?
As I said previously, my 2011 Supersports engine has the 87° thermostat, not a 100°c nor a 105°c.
Just to be clear for others, the electric thermostat has no electrical control as to say any mechanical movement by electric motor or such, it is simply an electric heating element/rod that went into the innards of the thermostat to heat the wax, allowing it to open sooner than coolant temp would.
.
As @jeyjey said, something else may be going on, coolant temp sensor or such, I would hate to think it or say it, but as this happened after a somewhat aggressive run, and the radiator leaking, have you had the coolant and or reservoir checked for exhaust gasses, and or being overpressurized, as an issue concerning exhaust gasses would raise the coolant temperature extremely quickly.
Hello @Sal-Man ,
My mistake, I meant to write 2011 for your vehicle.
Your 2011 does not use any electrical thermostat, that stopped in 07-08.
As to your comment of your thermostat opening at 105°c, I believe that would be incorrect, as the 2008 and up used the non electric 87°c thermostat, not the 100°c electric one that the previous years used, and the 105°c electric thermostat was used in the 05-10 Audi A8L W12, I have one in my A8L W12, so, has anyone ever replaced your thermostat, where did you get the 105°c opening information from ?
As I said previously, my 2011 Supersports engine has the 87° thermostat, not a 100°c nor a 105°c.
Just to be clear for others, the electric thermostat has no electrical control as to say any mechanical movement by electric motor or such, it is simply an electric heating element/rod that went into the innards of the thermostat to heat the wax, allowing it to open sooner than coolant temp would.
.
As @jeyjey said, something else may be going on, coolant temp sensor or such, I would hate to think it or say it, but as this happened after a somewhat aggressive run, and the radiator leaking, have you had the coolant and or reservoir checked for exhaust gasses, and or being overpressurized, as an issue concerning exhaust gasses would raise the coolant temperature extremely quickly.
Johnny
.
I would doubt this has anything to do with exhaust gasses in my system because this happens intermittently, if there were gasses then of course it will always overheat.
What would be the reason exhaust gasses entered my cooling system?
Also my bad about the thermostat, I read about the older 2006-2007 opening temp which was 100 or 105c.
Also my leak is currently being repaired and the coolant is removed and will have to put fresh new coolant in there.
Also my coolant leak was before the aggressive run.
After that aggressive run, I parked the car for 4 days then went out for a drive and the temp creeped past 90c which scared me at first. I turned the heater at full max and stopped at the nearest parking area, but again the car recovers, the temp rapidly goes back to 90c, if it were exhaust gasses, I doubt the car would recover quick.
@Sal-Man ,
I only mentioned the exhaust gasses as an item for you to check, I didn't mean to make you defensive, it's a simple test at the coolant reservoir, first a simple look for bubbles while running, and someone giving it a little throttle on and off, the other is an actual test with test fluid changing color, along with possibility of bubbles.
As to the exhaust gas being constant, not always, I have had issues simular to yours on other brands of VAG and others, depending on temperature of the engine, a leak may be present at cold but not hot, or vise versa, I've had temp shoot up, then be normal, again, not the Bentley, but others, it was hot exhaust gas into the coolant system.
Remember, our turbos are not only oil cooled / lubricated, but have coolant lines to and from each turbo, therefore an issue with either turbo could allow exhaust gasses, not just either head gasket..
As I said, I would hate to think it or say it, I only mentioned it for you to test and check off as a possible issue.
@Sal-Man ,
I only mentioned the exhaust gasses as an item for you to check, I didn't mean to make you defensive, it's a simple test at the coolant reservoir, first a simple look for bubbles while running, and someone giving it a little throttle on and off, the other is an actual test with test fluid changing color, along with possibility of bubbles.
As to the exhaust gas being constant, not always, I have had issues simular to yours on other brands of VAG and others, depending on temperature of the engine, a leak may be present at cold but not hot, or vise versa, I've had temp shoot up, then be normal, again, not the Bentley, but others, it was hot exhaust gas into the coolant system.
Remember, our turbos are not only oil cooled / lubricated, but have coolant lines to and from each turbo, therefore an issue with either turbo could allow exhaust gasses, not just either head gasket..
As I said, I would hate to think it or say it, I only mentioned it for you to test and check off as a possible issue.
Johnny
.
I will take a look at that but hopefully it is not the case.
This is a low mileage car 80,000km and that would be devastating because it will be quite a big job to replace the gaskets. I am praying that it is something small like due to the small leak when I did the aggressive run and when I parked the car, some air got into the system. That is because at some drives this would happen and at some, it never happens at all.
Last time, before the dealer saw the gauge climbing, the technicians did a few aggressive pulls and the temp never went over 90c, but now this is the actual message from the dealer.
“Good afternoon Salman, parts have arrived the tensioner is fitted also the ac valves, we can’t find any further leaks on the ac
Overheating we have witnessed it happen from bringing the car from upstairs parking to the ramp the temp shot past 90 degrees, the engine is not actually overheating especially in such a short drive, we have tested the temperature sensors and these are ok aswell as the wiring to them
For this issue you need to replace the exhaust gas temperature sensor as this can cause the car to think it is overheating.”
