Can anyone out there give me any advice on what could be going wrong with my 2004 Saturn Vue. I have had the coils changed out three times now because of problems and they are going out again. I take the car to a mechanic but I am still trying to figure out what the heck is going on I keep getting the P 300 code. I take it back they put factory coils in it and after a month or less we are back to having the same problems again it has been warranty work so I am not getting charged other than the initial change of coils I am just trying to figure out other things to check

 

I'm not a mechanic, but in my 45+ years of tinkering with cars, if coils keep going bad, there's usually been a problem with a loose or defective ground somewhere in the wiring. Good luck with it.

 

Have they pulled the plugs and checked for gap or damage issues?
3 months of driving issue free + replacement coils "patching" the problem only to reoccur again sounds like the coils are not really the direct cause,

Check the condition of the boots at the spark plug. If your valve cover gasket is bad around the spark plug wells, oil will seep into the wells where the spark plugs enter the block.
If this is not attended to, once the oil gets up to the bottom of the boot, it can get sucked up via capillary action up to the top of the plug, creating another current path for the current to follow, ultimately NOT through the plug and therefore a misfire. And not all the time. Hence random.

I would also suggest you pull the plugs and carefully inspect for arcing to places other than the electrode.

I would think any auto shop would immediately notice this. I know from working on exactly 1 Vue that if it is a V6, the back 3 cyls are a bitch to get to for pulling plugs unless you dismantle stuff. But you should at least be able to get the boots off (pull by the BOOTS NOT THE WIRE) and use a mirror to inspect the wells and you'll be holding the boot in your hand, which you can inspect for oil seepage.

If you find oil, clean off the boots as best you can (all of them. Try to get to the metal electrode clip but dont't use anything that will tear and stick in there and not come out. If you can make the P0300 go away on your own, you've likely found the problem.

Do not let them sell you an ignition control module until you have investigated the potential oil seepage issue.

 

I had the same exact problem. I replaced my coils 4 time, and my plugs twice. I recently found that each time I did the replacement, my engine ran fine for a period of time. The coil pack harness is my problem. It has a shortage in it and each time I moved it, my engine ran great. The 04 Saturn Vue is known to dry rot inside the wire housing. Mine has the issue on bank one harness. 1 and 3 were constantly misfiring.

 

7-year-old post but still very valuable information. Thank you