I drive a BMW e46 320i 2001 model, I changed a clutch kid, petrol pump, spark plugs oil and oil filter and oil separator but still it increases the speed slowly especially in the morning when it is cold but during a hot day it performs much better. The temperature gauge takes a very long time to reach the optimum/operation temperature. What could be the cause of this problem guys?
My car has a manual transmission.
Your issue seems to be temperature related. Taking too long to reach proper operating temperature can be cause by two things. First thing I would check is if either the electric cooling fan is running all the time no matter the temperature. Related would be checking the engine-driven fan clutch. If the fan clutch is seized, then it may be pulling too much air through the radiator when it is not needed. Secondly, I would check to see if the engine thermostat is stuck in the open position. The thermostat should remain closed until the coolant reaches proper operating temperature. If you would like to consult an expert to see this in person, a certified technician from YourMechanic can come to your home or office to inspect your vehicle’s loss of power and let you know what needs repair.
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