Having problems with your 1999 Chevrolet Silverado 1500 ?

5.3 L Missing and Rough Idle Intermittently

\015 I have changed Spark Plugs,Wires ,Coil Packs, and removed Fuel Injectors and soaked overnight. Engine code is a P0304. Misfire Cylinder #4. Most of the time around town is alright. When i put it on highway, it will surge like its cutting off and then pick right back up and be fine. Fuel Presure is 55 psi. Fuel Pressure Regulator is good. I do have faulty gas gauge but I replace fuel pump about 2 years ago. Sometimes when sitting at stop light you can feel motor lope a little and RPM's fall to about 300. I am running out of ideas. I swapped fuel injector on 4 cyclinder thinking the misfire might follow injector for trouble shooting. So far no codes.....\015 Posted / edited by AnonymousUser on : 15-01-2018

Answers :

I have a 2001 chevy z-71 5.3L. I keep getting a random/multiple misfire code for cylinder 1 . I have replaced plugs, wires, coil pack(only on #1 cylinder)., and fuel pump. I still keep getting the cylinder 1 misfire code. I put truck on a scanner and watched the cylinders. # 1 misfires at idle but quickly stops misfiring at around 1000 rpms. you can here the engine miss at idle but truck runs great on road . anyone else ever had this problem?
It could possibly be a bad crank sensor. generally when that goes bad #1 cylinder is your issue though
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