I've been having some misfires, took my plugs out and this is what they look like.

2006 xb AT

Greddy Supercharger w emanage.

55k miles

The plugs are in order from cylinder 1 on the left to cylinder 4 on the right. I got misfire codes on cylinders 2 and 4 as well as random cylinder misfire.

I recently changed air intakes and now I think the old one had a vacuum leak somewhere because the performance improved after I installed the factory air box.

Any help would be so much appreciated. I've been googling and looking at charts but these plugs seem to fall somewhere in the middle of a few conditions.

The plugs in the pic ar NGK Iridium BKR7EIX

 

The coloration is caused by the additives in the gas , MMT if I remember right. They added it to replace the lead in our gas.Seems to be normal looking for used plugs with many miles on them , specially when boosted and running the needed colder plug.

By the way, on boosted application you should use copper plugs 1 to 2 ranges colder , iridiums will misfire because of the tip design , so will platinum. The flame kernal will be "blown out " by the incoming air/fuel mixture.This will cause alot of the buildup your seeing.

 

One of the best little books I have has this photo in it:

http://www.aa1car.com/library/reading_spark_plugs.jpg

...and just agreeing with frogbox there, look for some colder plugs

 

Did you check the gap? As plugs wear, the electrode erodes and the gap widens, sometimes to the point where it stops making a spark. I always run the standard copper v-power, they'll last 30,000. For $8, you may as swap in a new pair of copper and see if the codes go away. For NGK, the colder plugs have a bigger number, so you'd go from a 5 to a 6. 7 is probably too cold for the supercharger. 5 is stock, gap is .032". Try BKR6EYA or BKR6EY.

 

post a smaller picture

 

Thanks so much! That's very useful information. I saw on a post that those bkr7 plugs were recommended for the s/c. For some reason I went with those. I HAD flour something else back in there after I saw the condition of those plugs and V Power BKR5 is what I had on hand, so they're in there now. I'll get some bkr6's soon.

I did the redneck vacuum test (didn't start a fire) and couldn't find any leaks.

Thanks again everyone. I'll give an update soon.

Dennis

 

The word flour should be "to put " oops

 

You Baking a cake, pie , or bread while you post?

 

Damn auto-correct!

 

Thanks for the help guys but today I got a P0354 (ignition coil d primary/secondary circuit fault) trouble code. I noticed, when I changed the plugs, there was a few drops of water down under the coil pack. I'm thinking that could have caused a temporary short. The car is running good today but I can't get more than, like, one pound of boost. I know the belt isn't slipping and actuator (bypass valve) is moving freely and not touching the wiring harness.

I want to test for a vacuum leak again and swap the ignition packs (three and four).

The sky is falling! Please help!

 

Well, I swapped coil packs three and four, cleaned the MAF sensor and replaced the PCV valve. The PCV was still jiggling but it had some oil in it so I replaced it. I redid the vacuum test and I may have found a leak where the supercharger meets the block, kinda close to cylinder two. I suppose I will pull the supercharger, clean old RTV and replace with blue RTV. I accidentally used red when I installed it. I'm not GLAD I found a vacuum leak, but I hope I have found the root cause of my problems, including those BURNED-THE-HELL-UP spark plugs.

any thoughts?

 

Almost forgot, also got a P0171 (system too lean, bank1)

 

The P0171 makes sense if you have a vacuum leak. Definitely seal up that s/c, could be the root of all your problems. Im using copper plugs one step colder with a gap of .030 and it runs great. Since I put in 1ZZ injectors, I haven't been leaning out anymore either.

Edit** Also, do those two middle plugs have oil on them? If you have oil leaking into the spark plug holes then you need to replace the valve cover/seals around the holes.

 

The plugs are dry but they do look terrible.

Am I maxing out my injectors? Should I get the tc
injectors?

Thanks so much
Dennis

 

I think TC injectors are too much, you'd run really rich. Even just with 1ZZ corolla injectors mine runs rich now (except 5000+), so i'm heading for a proper tune next week.

 

I do believe my emanage is factory tuned for my car and "locked". If I got bigger injectors, I'm not sure I could retune. I thought the ecu would compensate for a bigger injector, but I know it the stock injectors can't do more than %100. if that makes sense.

Is there an injector you would suggest for me?

Guess I'll go ahead and get a new coupler while I'm at it.

 

Ok ok ok. I have confirmed a leaking diaphram in the actuator. That could explain a lot.

Tell me your thoughts.

 

I have the unlocked base map for the supercharger direct from Greddy if you need. I got them to send it to me because the one that comes on it was locked.

 

Let me get this thing mechanically sound first. I finally found anther bypass actuator online from a place that takes paypal! IT IS ON THE WAY!

That basemap, is it just a generic starting tune or the one for the xb? Sorry if I missed that.

Thanks again,
Dennis

 

Those plugs are either too cold or your engine is running rich...so, everyone that is telling you to go to golder plugs are not correct for this engine. The number 4 plug is positioned wrong to read. Even my read here from these pictures is NOT GOOD! Set your camera to macro, and take a real closeup of the inside of the plug...so we could see where the ceramic meets the steel. That is the place that tells you if the plug is too cold or too hot. The edge of the rim (end of the threads that are shown in your photos) tells you how clean you engine is running...yours are black...either your engine is eating oil, or it is running too rich.

Other people here have given you good tooning advice...try those...