I just installed new plugs, 24# injectors, and a superchip tuned for everything on my truck. Do you guys think that improperly gapped plugs would cause my microtuner to spit out DTCs P0300 and P0304 (mutiple cyclinder misfire and cylinder 4 misfire)? Or could it be caused by the new injectors? I'm kinda leaning toward the spark plugs being gapped wrong, what do you guys think? I need help!!!

 

Does it sound or feel like it is missing. Could you have crossed up a couple of wires when you did the plugs ? Unless the gap is completely closed I don't think you would have multi- misfires even with a big gap.

 

It is idling extremely rough, and stalled out on me for the first time ever. I plugged my tuner in to see if my computer would spit out any codes and it did. According to the codes it is misfiring, and well when you run the engine you can tell as well. I am going to go back and check all the wires and hoses to see if they might be the culprit, but I could still use a little more advice. I did just install new injectors as well, do you think that a bad injector could cause something like this?

 

The only code that my truck is reading now is P0304 which is the #4 cylinder misfire, but I haven't driven it to see if the P0300 random and multiple misfire code shows up again. Any advice would help. Thanks