A short to ground. Check wiring/sensor for damage.
Tail light assembly short
it can be caused by a bad alternator
There must be a short in the system somewhere that causes the fuse to blow.
could be the fuse
This is the starter fuse I am talking about. It doesn't blow every time. It might go weeks before it blows again.
to many plugs in at once or old circuits ECT.
there is a short some where check the wires as well as the oxygen sensor.
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Ck the heater fan motor resistor .
Need to know which 20 Amp fuse is blowing.
no A FRN fuse is a slow blow fuse where an non is a fast blow fuse. In a pinch a slow blow fuse can be use in a fast blow circuit but not the other way around.
The O2 sensor isn't fused. It plugs straight into your ECU.