Well, a couple things come to mind. If this is the 86 in your sig, I'm not as sure, but I know on the 96+ OBDII systems a flashing light means a misfire.

The other thing you might consider replacing is your thermostat. If it's stuck open, your truck will not get hot enough, and the O2 sensor will complain.


My Truck: 1987 XtraCab DLX 22R 4WD 5 Speed Manual
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"Speed has never killed anyone. Suddenly becoming stationary, that's what gets you." -Jeremy Clarkson