Well it appears that I may have spark blow out. I removed my heat range 8's spark plugs and replacd them with 9's. I took the car around the block today and I took it up to 8K and when I shifted gear and got back into it nothing happened when I pressed on the gas. I let off shifted up and then everything was fine. This happened to me twice. I measured the 9 plugs before installing them and they apeared to be gapped at .30". I noticed when I plugged into flashpro I had a DTC for 1 & 4 misfires. I regapped the plugs down to .22" and swapped coils #1 with #2 and #4 with #3. I haven't driven the car since.

Any thoughts from anyone?

Update 08/04/11- Guys im still having issues with my S2000 I get miss fires on ALL cylinders and I am out of ideas other then replacing coils and the battery. I have tired running 8's and 9's gapped to .020" on race fuel and I get the same thing. I have tried 8's gapped to .020" on 8lbs and 93 octane and I get the same thing. My car on has 12K miles on it and would hate to have to buy new coils. Anyways which ones are the best? Should I try a new battery first? If so which one? I even added a ground to the back of the valve cover and no luck. I adjusted the valve and all were within specs or .001" out but we adjusted them on the tighter side.

Update 08/05/11-well I had the battery tested and it came back with 340 CCA and its rated for 410 with a 12.97 Voltage reading. To me that sounds fine but all three different places said the battery is a little less then half of its state and needs replacing. Does this sound right? Should I just replace it due to my misfires?

Update 08/08/11- I replaced the battery and no difference. I took the car to a shop and put it on a dyno. Fuel pressure is 60psi base (vacuum unhooked) and ~55psi at idle. During the pull the fuel pressure climped to ~80psi at redline and 18psi. We also swapped in some RSX coils and no change. I did realize that it only misfires at higher RPM's and light throttle. The shop tired pulling 5 degrees timing in low cam and high cam light throttle and no change. He said the car pulls and feels great.

Final Update- So I did a few things and something seemed to correct the issue. First I noticed that my boost guage was showing ~19-20 psi but my datalogs only showed 13-15psi on the map sensor so I bought a new hondata 4 bar map sensor. I also found loose intake manifold bolts slightly loose. I also found tons of small boost leaks in the vacuum lines. A few things to also look into is...what are my light throttle high rpms A/F's like? mine were in the 15-16:1 area at times and Evans Tuning felt that I may have been getting DRY Miss Fires which will not cause engine failure due to there being no combustion occuring.

 

What is your power and how many miles on the coils? Main reason for coils to cause spark blowout is having some with high mileage. I am making around 775 whp on e85 (takes more spark to ignite) and no issues with spark blowout, but my coils only have 15k original miles on them. I also run NGK iridium 8's gapped to .018". Get a new set of coils and gap down to around .020" and you should be fine.

 

SOS 1200 blower. 520-540whp @19psi on Sunoco 104 Race fuel. My08 only has 12K on it. I was seeing miss fires on the 8's which appeared to be gapped down to .015-.018. I swapped the 8's for 9's and left the gap @ .030 and got the above issues along with miss fire on 1 & 4. I since then gapped them down to .022" and all apears fine(hopefully).

BTW the car was tuned for 17psi with a boost leak and IAT around 180-190 degrees (done on wednesday). I since then found the boost leak so I'm seeing 19psi now and bypassed the BOV lowering my IAT to around 120 degrees. I would like to send my datalogs to Evan for a touch up but I'm still waiting for my new primary O2 sensor to come in. He said I would be fine without it but my closed loop would hurt due to it. At WOT I am seeing 11.2-11.4 A/F ratio.

Edit Spooling I have read tons of posts with you chiming in on these type of issues.

 

I had spark blowout issues on my car with range 8 NGK's on meth/water. I went with a KB BAS and haven't had a problem.


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I've changed them out for 9's now. what all is involved in the KB BAS? any cutting into the factory wiring?

 

9's are kinda overkill for that power level. If you run too cold of a plug, it will cause misfires. I run 7's up to 600hp and 8's over that.

 

Damn lol. Isn't 7 stock heat range? And to think I thought my 8's would be to hot lol.

 

Alot of boosted s2ks are either on e85 or racegas. You want to run a hotter plug in these situations. I had a car on the dyno last week that made 420hp and were running the ngk 8's. These were a brand new set of plugs gapped from .030 to .020 and we still had misfires up top. I threw in a set of cheap ngk copper 7's gapped to .028 and it cleared up and made more power.

 

Alot of boosted s2ks are either on e85 or racegas. You want to run a hotter plug in these situations. I had a car on the dyno last week that made 420hp and were running the ngk 8's. These were a brand new set of plugs gapped from .030 to .020 and we still had misfires up top. I threw in a set of cheap ngk copper 7's gapped to .028 and it cleared up and made more power.
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Cool cool. For me on pump looking for close to 500. Which copper plig do u recommend? The 7173 8 range Ngk? I have the 2668 in there now. Thanks in advance.

/ threadjack lol

 

Alot of boosted s2ks are either on e85 or racegas. You want to run a hotter plug in these situations. I had a car on the dyno last week that made 420hp and were running the ngk 8's. These were a brand new set of plugs gapped from .030 to .020 and we still had misfires up top. I threw in a set of cheap ngk copper 7's gapped to .028 and it cleared up and made more power.
[/quote]


Cool cool. For me on pump looking for close to 500. Which copper plig do u recommend? The 7173 8 range Ngk? I have the 2668 in there now. Thanks in advance.

/ threadjack lol
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I would like to know the same also...I prefer copper NGK plugs over any thing else. Also I had 8's and it appears Evan gapped them to .015-.017. He said 9's would be best. I had mis fires the next night after the tune (lowed IAT and fixed boost leak before I ever drove the car). So I bought the 9's with stock .030" gap had what I think is spark blowout. Regapped them to .022" and it appears to be fine.