Good afternoon everyone. Having a big issue here. I have a 2000 Chevy Blazer 4.3 2WD. Went out to start the car this morning. Everything fired up as expected. After it warmed up while driving it all of a sudden there was a wicked misfire. It happend for about 500 feet then the tach went down to 0 and the misfire went away. After the misfire went away it seems as though I lost some power. Will be heading up to the autoparts store to get the codes here shortly. Any advise?

 

Report back with any codes you get. It is not outside the realm of possibility that the mechanism for the tach went bad after a voltage spike perhaps.

 

Tach is ran off a wire from the Coil, Check spark quality with a spark-gap tester and check if you are getting any output from the tach signal wire, i believe it is Wire C