Hey all! New user.

Title says it all, I've had my '03 coupe for a while now but I've been dealing with a problem off and on with a random misfire. Sometimes it will immediately start misfiring right after I turn the key, which I guess I fix by turning it off and back on until it stops. Other times it will happen randomly while driving & it either goes away on its own (depending on drive time) or I have to pull over and try to get it to stop. At the very least, I've tried isolating the issue by switching spark plugs and that isn't the issue, so what else could be causing it?

It's strictly throwing code for Cylinder 1 if that makes a difference. This isn't my daily and the car is a backup now so I'm not super worried about it, but it'd be nice if it were halfway reliable.

 

I've read through some related problems right now and found some stuff I need to try out e.g. switch coil packs. My rear main is shot too which someone said a bad oil leak could cause issues so I'll address this stuff first and see what happens! Amateur hour not checking the forums first.

 

First step, replace ALL the spark plugs. Clear codes, see if it comes back. Plugs are cheap and easy compared to other components and they make a huge difference in how the engine runs. Part number PLFR5A-11

Random misfire code - P0300

Cylinder 1 misfire code - P0301

Exactly what code are you getting?

 

Sorry but if it continually gives you a code for cylinder 1, then don't you think cylinder 1 just might be the issue? Swap coils with another cylinder and see if the code follows it - I'm betting that it does. You need a new coil.