Hey guys,

So the past week I've been doing some work on my car. My O2 sensor died so I had to replace it. While doing so I used one of those rrm catalytic code remover things on the other O2 sensor to get rid of my cat code. Then found out my car was running too lean from a hole in my exhaust . Got that fixed yesterday, but now a new code popped up after getting that fixed. The P0300- random/multiple cylinder misfire.

Could it be my spark plugs? I have the iridium NGK IX's in there now. Could it be that they got messed up or dirty from my car running lean? They're about 20k old and haven't had a problem.

Or is this code from something else?

 

From the service manual...

First thing I'd try is an ECU reset, which will make the car readjust the fuel trims. If the code returns, then I'd pull and check/replace the spark plugs.

 

Hey thanks! I did actually do a reset when the weld was done but thats when the code popped up. Yesterday morning I looked underneath and saw more exhaust coming out, but in little holes So my mechanic doesn't know how to weld very well, but got it fixed again.

Looks like I'm 80 miles in and no CEL *knocks on wood* But I will look at my plugs if that code pops up again.