PlasticMac
Admin Team
Serious engine damage has recently resulted from overheating in two FSIs.
The cause of the overheating, in both cases, was failure of the heater element in the thermostat housing.
This heater element is used to lower the engine temperature, from the normal 110C, to around 85C, by opening the thermostat early when the engine load is high, to dissipate the extra heat through the radiator, and keep the engine at a safe temperature.
When the heater element fails, the EML will tell you, but the thermostat will now only open at 110C, so no additional cooling at high engine loads. At these higher loads, the engine will overheat, causing engine damage, most likely head gasket failure.
Sadly, when the EML is on, it's not unknown to hear "Yes I've got an EML, but the car runs fine, so I ignore it ..."
Yes, it will run fine ... until it doesn't, but it'll be too late by then. If you see an EML, scan it, don't leave it.
If the heater element is the problem, a scan will show:
<17704/P1296/004758 - Error in Mapped Cooling System>
Best not drive the car, until the part is replaced, or risk the of the engine overheating is high.
Although this heater element failure applies to all FSIs, perhaps it is, potentially, more likely when the engine is running the ProBoost ECU.
This is because the ProBoost map runs the engine at the lower temperature, (85C), at all times, and does this using the heater element to open the thermostat at the lower temperature. This will mean that the heater will be on much of the time, so it's very likely it's life will be shorter in a Proboost engine, than one with the OEM map.
EML is your friend, not your enemy. It could very well save your engine from destruction.
Mac.
The cause of the overheating, in both cases, was failure of the heater element in the thermostat housing.
This heater element is used to lower the engine temperature, from the normal 110C, to around 85C, by opening the thermostat early when the engine load is high, to dissipate the extra heat through the radiator, and keep the engine at a safe temperature.
When the heater element fails, the EML will tell you, but the thermostat will now only open at 110C, so no additional cooling at high engine loads. At these higher loads, the engine will overheat, causing engine damage, most likely head gasket failure.
Sadly, when the EML is on, it's not unknown to hear "Yes I've got an EML, but the car runs fine, so I ignore it ..."
Yes, it will run fine ... until it doesn't, but it'll be too late by then. If you see an EML, scan it, don't leave it.
If the heater element is the problem, a scan will show:
<17704/P1296/004758 - Error in Mapped Cooling System>
Best not drive the car, until the part is replaced, or risk the of the engine overheating is high.
Although this heater element failure applies to all FSIs, perhaps it is, potentially, more likely when the engine is running the ProBoost ECU.
This is because the ProBoost map runs the engine at the lower temperature, (85C), at all times, and does this using the heater element to open the thermostat at the lower temperature. This will mean that the heater will be on much of the time, so it's very likely it's life will be shorter in a Proboost engine, than one with the OEM map.
EML is your friend, not your enemy. It could very well save your engine from destruction.
Mac.