Hi I am new to the forum so thanks ahead of time for the help, because I am truly stumped. My blazer is a 1997 with 180,000 miles on it. I had parked it one night, and it was running and driving normally. I went out the next day and it was misfiring and I had no gears at all, it's an automatic transmission. I have no turnsignals and also no lower brake lights or hazards. It was throwing a po300 code. I replaced the fuel injectors, battery, spark plugs, distributor cap, and ignition coil. It was running almost perfect but still no gears. I changed the oil and filter and I have all forward gears but no reverse, and now it will drive forward in neautral. After changing oil, I went to start and it runs but like it has no power. I ow have a p1351 code and a po304 code. I am out of ideas and I don't know where to look anymore. Any help would be greatly appreciated. Thank you!

 

The p1351 is for the Ignition control module having high input conditions. I would start by replacing that and see if that fixes that code. And the P0304 is a misfire in cylinder 4 and the possible causes could be from Faulty coil pack, sparkplug or wires, oxygen sensor(s), or fuel injector. Take your pick on where to start, but I would check the wires if you haven't replaced them.