jeffroid Posted August 20, 2013 Share Posted August 20, 2013 I have a '96 outback with the 2.2L and 5-speed. It started misfiring under load and finally threw the P0302 CODE. It happened right by the parts store so I just cleared the code and it didn't come back right away. Still misfiring under load but not bad. I looked under the hood after dark and there was no arcing or sparking of the plug wires even while misting water around the coil. After a couple of days the code came back. It was finally the weekend so I had time to pull the plugs. They all looked like the text book picture of what a perfectly firing plug should look like but were hugely over gapped, probably near .060". I regapped them and put them back in to see what would happen. That made a big difference. It was running way better. It still felt like I could make it misfire or stumble or whatever by intentionally lugging it in too high a gear, so on the way home from work yesterday I bought new NGK's and went home to change them. Of course since I was in a hurry the first thing that happened was that the plug wire pulled out of one of the spark plug terminals. I didn't have time to go buy new plug wires so I repaired it the best I could with a screwdriver and needle nose pliers. I'm going to order up a new set of NGK wires this morning. NOW to my main point. It wasn't until after I had a couple of the plugs in that I noticed I had purchased BKR5E11 plugs. The plugs that came out were BKR6E11. I just put them in, put everything back together and took it for a quick run on the highway. It ran AWESOME. No sign of misfire or stumbing under load. So this morning I am doing some research and I get conflicting information on whether the 5 or 6 is the right plug to use. It looks like it probably should have been the 6. Interesting that if I go to the NGK website and punch in the 2.2L for the '96 outback it tells me to use the 6, but if I punch in the 2.5L it tells me to use the 5. I also found this part number decoder which I thought was pretty cool: http://www.ngksparkplugs.com/docs/tech/design_symbols_plugs.pdf So I am thinking that I probably should have went with the 6, especially since the 6's that I took out looked like the text book picture of what a plug should after around 100K miles. Do the experts agree that I should be using the 6's? Is running with the hotter 5 plug really that big of a deal? Do the experts think I should eat the $10 bucks and buy a new set of 6's to go with the new plug wires? Or should I not worry about it and just go with the 5's? Thanks to all who bothered to read this far. I have a tendency to write novels. And I did do a search first. Quote Link to comment Share on other sites More sharing options...
lmdew Posted August 20, 2013 Share Posted August 20, 2013 Either should be fine. Not that much of a difference. Make sure you get Subaru or NGK plug wires. Quote Link to comment Share on other sites More sharing options...
ivans imports Posted August 20, 2013 Share Posted August 20, 2013 If it dont say NGK throw it away !!! 1 Quote Link to comment Share on other sites More sharing options...
rverdoold Posted August 20, 2013 Share Posted August 20, 2013 As long as you do not run on Propane (LPG) the 5 should not give any problems. At next change check how the colour looks like. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted August 21, 2013 Share Posted August 21, 2013 No harm done running the 5 plug in the 2.2. But you do have a point, its interesting that they spec. the 5 for the higher compression 2.5 engine. Seems to go against conventional wisdom, but I'm sure Subaru had a good reason to use a plug with that heat range. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.