trouble code

[86grdnatl]

a trouble code came up on my 86 gn so i plugged in a gm scanner and got a trouble code of 45 which means rich exhaust indication- oxygen (o2) sensor voltage says high after one minute of engine run. (Left sensor on dual sensor engines). Just wondering if anyone knows what this means or how i could fix it? Thanks

 

[RmvBfrFlght]

For some reason the ECM can't bring the O2 level in the exhaust down. You will likely find both the INT and BLM bottomed out. This can be caused by a bad O2 sensor (silicone poisoned), but this usually leads to the engine going lean and cutting out.

Can also be caused by the fuel pressure being too high, or an injector is leaking, or the FPR diaphragm has a leak in it (fuel going into engine via the vacuum line).

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