2002 Chevrolet Trailblazer Got Flashing Service Engine Soon Light Manual

the flashing light indicates that there is a catalyst damaging missfire going on.do not drive the vehicle ,you can wipe out your catalytic converter.you have to determine what cylinder or cylinders are missing and why.it could be anything from a plug,to a fuel injector.i will say this these engines have a huge amount of distributor cap and rotor issues that cause all kinds of crazy missfires.i would start by checking the distributor cap and rotor for corrossion and wear.