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How does one test a coil pack? (updated w/ photos)
The title basically says it all. I assume there is more than one way, or maybe not, checking voltage maybe?(if so what reading is standard in working condition?). Before you ask, yes; I have tried the wonderful search bar with no avail. My 04 vq35de is throwing the p0300 misfire and I want to troubleshoot before I go ***** deep in my wallet . Thanks in advance.
Oh and p.s. this will be my first post on here in nearly 3 years. help a brotha out!
EDIT 2/18/2015
Originally Posted by i8acobra
Before you test the coil, did you pull out the plugs? Are the tops covered in oil? A P0300 is a multi-cylinder misfire, highly unlikely it's a bad coil. If the plug tubes are full of oil, you need valve covers. It's the most common cause of a P0300 on a VQ35. Second most common is worn out plugs.
After digging in I have a little oil in the #5 cyl and a good amount in the #6. I also took my intake manifold off (to make it easier) and found a lot of unburned (I think) fuel in the #1,3,5,6 cylinders, do I have a bigger problem on my hands?. the plugs however are clean, minus the oil. see the pics below and please let me know what you think.
thanks everyone in advance for any help.
Last edited by my-red-pony; 02-18-2015 at 03:34 PM.
Reason: Updated with a bigger problem? i think.
I forget but there is a procedure in the factory service manual - IIRC you are testing resistance. I have 3 or 4 coils left over from a part out if you are looking to replace just a single unit.
Before you test the coil, did you pull out the plugs? Are the tops covered in oil? A P0300 is a multi-cylinder misfire, highly unlikely it's a bad coil. If the plug tubes are full of oil, you need valve covers. It's the most common cause of a P0300 on a VQ35. Second most common is worn out plugs.
Pull it off the spark plug, stick your peepee in the end of the plug boot and grab your negative battery terminal.
If you aren't manly enough to do that, you can move it to a different cylinder. See if the misfire code follows it to the new cylinder.
My peepee is too small for that technique but I will definitely try swapping back and forth. Thank you.
Originally Posted by bealljk
I forget but there is a procedure in the factory service manual - IIRC you are testing resistance. I have 3 or 4 coils left over from a part out if you are looking to replace just a single unit.
I read in a post somewhere to check for a 12v output but I have a hard time fathoming that. I will definitely PM you for a price if that's what I need, Thank for sir!
Originally Posted by i8acobra
Before you test the coil, did you pull out the plugs? Are the tops covered in oil? A P0300 is a multi-cylinder misfire, highly unlikely it's a bad coil. If the plug tubes are full of oil, you need valve covers. It's the most common cause of a P0300 on a VQ35. Second most common is worn out plugs.
I am going to dive in to it after work today and troubleshoot the problem (check for vacuum leaks, bad wire connections, plugs, and seals)- I just figured since I have the coil packs off during disassembly maybe there was a way to check the voltage or something like that. I didn't even think to check for a bad cover- thank you, I will definitely be checking for that as well!
02-17-2015, 07:11 PM
How does one test a coil pack? (updated w/ photos)
. Thanks in advance.
