Just curious, because I filled up the tank on my 2003 and then ended up getting a P0305 code (cylinder 5 misfire).

The car still runs and drives ok but I'm a bit worried driving on a misfire is NOT a good idea.

Before taking the spark plug out, I was wondering; fuel additive and a little premium gas maybe AFTER this tank has gone through?

any advice guys?

 

The reason I ask is that the spark plug job is a PAIN in the *** I've read and I really do NOT want to invest all that time and money for new plugs/wires and everything IF it's just a simple fix.

 

Plugs and wires are not that bad and CAN be done without removing the intake. I did it in about 2 hours.

 

Is there an easier way to do it? It seems like there's not very good instructions online. But BEFORE I proceed, could I just put premium in + fuel additive (I got a bottle of Seafoam in my garage) and just see if it'll fix?

 

No to your question

 

I never use Premium, might give you a little more power, maybe. No down side.

 

Thanks. In the future I'll definitely put in 93 as well.

 

No reason to run 93 octane in these old LR's. They have knock sensors, and they aren't race cars and they aren't what I'd call serious tow vehicles either (vs a Chevy/Dodge/Ford Pickup). The spark plugs themselves are about the easiest on the planet to get to engine wise. Coil Pack's are bit of a PITA, but if you don't have SAI you can get to the plug wires without removing the upper intake. I personally have it down to an art that it takes me no time at all to remove the upper intake.

 

Maybe you could just remove the plug from 5 and inspect it. See if it is fouling with coolant sludge... You've mentioned this misfire on 5 in previous threads with no resolution.

 

Update: changed plug #5 this morning. CEL went off for now (knock on wood). the plug hadn't been changed in years most likely. I'll get around to doing the plugs and wires soon because I know those are a disaster and need to be done eventually.
thnks for the help everyone.