97 blazer 4dr 4wd automatic: replaced cap, rotor and plug wires due to random miss fire code setting. a couple weeks later develops this new problem. idleing rough running rough fuel gauge needle bouncing up and down which seems to correspond to the roughness of the rough idle. needle holds steady under acceleration also needle spikes if i shift back an forth between drive and reverse, drive spikes, reverse spikes, drive spikes and so forth. also the service engine soon blinks continuously steady.

 

The blinking check engine means a severe misfire. Not sure about your other symptoms

 

Maybe your fuel injectors need a good cleaning??? Just a thought but try pouring a bottle or 2 of SeaFoam gas treatment in your gas tank next fill up at the pump... I swear by the stuff, it really smoothed out my ride.

 

go chevy: although i recently replaced the spider and poppets (fuel injectors), i will try the sea foam cleaning since it can't hurt.

cleburne red: im aware blinking service engine soon light might indicate severe misfire (it does indicate other problems) i am interested in answers for my other symptoms.

thank you both for your replies