Hey guys...titles says it got a p90300 code if i remeber correct, its a random multiple missfire. Looked at the wires and they seemed A okay, even repalced them with a set I had laying around and the code came back after i cleared it. I bought some new plugs, havnet got them in yet, but any other idea's on my im getting a Random Multiple Missfire?

 

wires arcing out on the headers??

 

yah none are touching...they are JBA wires...?? nice nad thick jacket on them...

 

Is your top end sluggish? Do you still have cats? I was getting tons of random misfire codes and had now power above 4000 rpm in our old grandprix when the cats got clogged. Another member here had a similar problem with his truck recently.

 

got cam?

 

What torque converter are you running, sometimes aftermarket converters cause that code. Another symtom of that would be the converter locking and unlocking randomly at highway speeds.

 

had a friend with p0300 random misfire 2003 silverado 5.3L. Heads damage
water in cylinders. You might want to check yours.

 

same here just pulled that multiple cylinder misfire code p0300

 

It's most likely from the cam and your stall-you need some adjustments on your tune.

 

hmmm....didnt know cam/stall would cause that.....

I will ahve steeda look into it