E3 spark plugs throwing codes! FYI

[ramairuss]

I decided to do a tune up on the old KJ and got those e3 plugs. Soon thereafter it started running like crap and throwing all kinds of misfire codes. Just to be sure I checked all the coils and made sure each produced spark with an old plug and a plug tester. As soon as I put new OEM plugs (NGK) back in it ran great and the CEL did not come back on.

 

[SurfGuitar141]

Never heard of "e3" spark plugs before.....

I put Autolite Double Platinum's in mine not long ago, it runs better, improved the mileage a bit, and no codes......

 

[ptsb5a]

I decided to do a tune up on the old KJ and got those e3 plugs. Soon thereafter it started running like crap and throwing all kinds of misfire codes. Just to be sure I checked all the coils and made sure each produced spark with an old plug and a plug tester. As soon as I put new OEM plugs (NGK) back in it ran great and the CEL did not come back on.

Just a shot in the dark here but I bet that the coil packs on the 3.7 don't pack enough punch to effectively light off an E3 plug. Even running Iridiums is a stretch for the coils. Until MSD comes out with an Ignition Controller and some zappy coil packs for us we're limited to running copper or platinum plugs.

 

[desertkj]

I had the same experience. I didn't have a CEL illuminate, but my Jeep started running much worse after I put in Bosch Platinum+4's. I also lost about 5 mpg (700 mi trip to California and I averaged 16 mpg highway. I usually get 21 mpg). OEM NGK's or Champions seem to be the best choice for the KJ.

 

[tjkj2002]

Just a shot in the dark here but I bet that the coil packs on the 3.7 don't pack enough punch to effectively light off an E3 plug. Even running Iridiums is a stretch for the coils. Until MSD comes out with an Ignition Controller and some zappy coil packs for us we're limited to running copper or platinum plugs.

Not why those type of plus do not work well in the 3.7 and 4.7's(and 5.7's also).Our ignition systems are called "waste" spark systems and having different materials in the plugs,copper core and platinum tips, screws up the system.Nothing wrong with this type of system,just need to buy the correct plugs is all.

 

[jnaut]

I had the same experience. I didn't have a CEL illuminate, but my Jeep started running much worse after I put in Bosch Platinum+4's. I also lost about 5 mpg (700 mi trip to California and I averaged 16 mpg highway. I usually get 21 mpg). OEM NGK's or Champions seem to be the best choice for the KJ.

I tend to be wary of the multi-electrode type plugs.

I used the Bosch Platinum Plus' (single electrodes) and the Jeep's running like a top. I have about 14,000 miles on those plugs now.