Odd plug readings
05-23-2005, 09:05 PM
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Odd plug readings Well some of you might recall my earlier posts about my high RPM miss. I haven't located the problem but fouled out my plugs in trying to do so. So I chnged them today. The front half of the motor (cylinders 1-4) are pretty normal looking. The back half (cylinders 5-8) are solid black. Injector pulsewidths are good. BLMs are 128. Plugs were NGK TR55's with a .035" gap. O2 voltages are similar and in decent range. It's not the Delteq cuz for example the 4 and 7 cylinders are on the same coil. Anyone seen this or can you at least point me in the right direction?
05-23-2005, 09:09 PM
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i know stock gap is at .050", but why gap them at .035" with TR55's? I see your using the Delteq, does that require you to gap them a lil smaller.... OR are you running the n2o on these plugs??? i would use a colder plug like the TR6 with n2o...
05-24-2005, 03:25 AM
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Well I myself didn't install the Delteq. I was at school (long story). So the guys that did it changed my plugs but instead of going back to TR6's (which I had), they put TR55's in (why I don't know). But there was no juice run on them. Since I've had juice, I've gapped my plugs tight however.
05-24-2005, 06:41 PM
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Hmm. So you have the same problem with cylinders 5-8 being black? I put in some cheap copper Champion plugs until I can figure out my upper rpm miss. Didn't wanna foul out $2.25+/ea NGKs when I can foul out Champions for $1.28/ea.
05-25-2005, 02:11 AM
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Yeah it's basically the same problem. At 1st I thought it was the alternator since it was dipping when I got up high in the rpm's. Changed it and still got the miss. Pulled the plugs and the 4 up front are burning great but the back 4 are close to being fouled. I'm not sequential either but batch fire so it's really a mystery to me.
05-25-2005, 10:48 AM
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That's really odd. Do you have the same high rpm miss I have? Above 5000 it just breaks down. I've reached the conclusion it's the opti giving the Delteq a bad signal.
