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Hello Guys,
I live in Dubai. We have super 98 petrol. This is first time I have put this fuel. I generally put 93. I have noticed my engine temperature rising. It generally stays at the 3rd needle but when I am driving for long duration. The temperature increases. Is it coincidence or there some thing wrong with the cooling system. I checked the radiator and coolant levels looks fine. Can higher octane increase the temperature. The needle is moving upwards the longer I drive
Model :2003 Ls 430
2003 LS430 Owner's Manual specifies minimum 91 octane rating. Please note that the octane rating at the fueling station is known as Anti Knock Index or AKI, and is the average of a fuels Research Octane Number and Motor Octane Number [(R+M)/2].The RON is determined by using a special engine with variable compression ratio, and comparing the knocking qualities of a given fuel to that of reference fuels, isooctane and n-heptane, while the MON is determined by using the actual LS430 engine. That said, no benefit is gained by using higher octane fuel. Also, higher octane fuel does not increase engine temperature.
Hello Guys,
I live in Dubai. We have super 98 petrol. This is first time I have put this fuel. I generally put 93. I have noticed my engine temperature rising. It generally stays at the 3rd needle but when I am driving for long duration. The temperature increases. Is it coincidence or there some thing wrong with the cooling system. I checked the radiator and coolant levels looks fine. Can higher octane increase the temperature. The needle is moving upwards the longer I drive
Model :2003 Ls 430
Mileage?
Any engine work recently performed?
If original thermostat, replace it with original Toyota part.
Verify your cooling fans and system components (sensors, fuses, relays) are functioning.
When was timing belt/water pump serviced?
Were aftermarket parts used??
In your part of town, probably you encounter elevated temperatures.
Determine whether you have standard or thicker "towing package" radiator.
If original thermostat, replace it with original Toyota part.
Verify your cooling fans and system components (sensors, fuses, relays) are functioning.
When was timing belt/water pump serviced?
Were aftermarket parts used??
In your part of town, probably you encounter elevated temperatures.
Determine whether you have standard or thicker "towing package" radiator.
If the former, then upgrade radiator.
The car is high on mileage 186411 miles. I bought this car last year and I am not sure when the timing belt was changed. Does 2003 have a chain or a belt? Mine is a Japenese specs UL model.
Does timing belt wear to cause a rise in temperature? The temperature stays stable for 20-30 min of driving and it is only increased after a little longer duration of driving. It starts to increase
It should have a belt. An old timing belt won’t cause overheat, but an old water pump might. Good practice to change both at the same time since you are in there already. That will likely help highlight any other issues you have with the cooling system (if any).
When I checked the thermostat and I found it was already bypassed which means the coolant is always flowing to the engine. Anyways, I put a new thermostat but I don't think this can be the issue now as it was already bypassed. Let me monitor for a few days. Is it possible to check any codes with techstream
The car is high on mileage 186411 miles. I bought this car last year and I am not sure when the timing belt was changed. Does 2003 have a chain or a belt? Mine is a Japenese specs UL model.
Does timing belt wear to cause a rise in temperature? The temperature stays stable for 20-30 min of driving and it is only increased after a little longer duration of driving. It starts to increase
The LS430 is cooled by its radiator and 2 electric fans. The radiator works most efficiently while the car is in motion (cool air rushing through the radiator flowing in via the front grill), with the electric fans providing the same when the car is not moving sufficient fast. The thermostat restricts coolant flow to the radiator to allow the engine to warm up initially, and will reach full open position once the engine is heated up. For very low temperature driving, the thermostat may never fully open in order to maintain operating temperature. On the other hand, a worn/clogged radiator may not pass enough coolant to drop the coolant temperature even with the thermostat fully open. This may be what you're seeing for your car. You may consider upgrading to a "Tow-Package" radiator to provide additional cooling capacity.
The LS430 is cooled by its radiator and 2 electric fans. The radiator works most efficiently while the car is in motion (cool air rushing through the radiator flowing in via the front grill), with the electric fans providing the same when the car is not moving sufficient fast. The thermostat restricts coolant flow to the radiator to allow the engine to warm up initially, and will reach full open position once the engine is heated up. For very low temperature driving, the thermostat may never fully open in order to maintain operating temperature. On the other hand, a worn/clogged radiator may not pass enough coolant to drop the coolant temperature even with the thermostat fully open. This may be what you're seeing for your car. You may consider upgrading to a "Tow-Package" radiator to provide additional cooling capacity.
I changed the thermostat and I think the problem is solved
Put higher Octane. Engine temperature increasing
