heater fan doesn't come on all the time , sometimes it takes 5 10 minutes to come on , changed thermostat , cleaned fuel injection , repaired exhaust manifold leak, engine run better but no fan
May be bad switch,or fan motor risitor.
All the work you did has nothing to do with the fan motor. There is a switch that turns the fan on and off. If the switch is bad, or the fan motor is bad, that is where the problem lies almost all the time. There could be a lose wire, but that doesn't sound like it. It really sounds like a fan motor is going bad.
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