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Discussion Starter · #1 ·
Hey everyone. So for some reason whenever I'm at a stop light, and I start to go I'll get up to -5.50 corrections on cylinder 3. Only happens in 1st gear. It'll add timing and then all of a sudden when I get to 3k rpm it'll start to pull timing. I just monitored knock count on cylinder 3 and it got up to 15 in the span of 1 second! I have K&N filter, flowmaster cat back, levels intercooler, cobb RMM and tuned. When WOT there's not a single negative correction to be seen. It was doing it back when I had the stock RMM and stopped doing it when I got the Cobb. Now that it's settled it seems to be coming back. Maybe time to go to CPE stage 2? Thoughts?
 

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Mine is doing this somewhat regularly too. Nothing but positive corrections up to +4 under any other driving conditions. But occasionally after leaving a light it will do this(cyl 2 or 3) Oddly enough it has never done it when leaving my driveway or stop sign on my road. I just had the driver and passenger side CPE motor mounts installed hopefully I'm just picking up some extra vibrations from them causing it. I asked Alex about it in my last email I sent him, waiting to hear back.
 

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Check your spark plug gaps and make sure they're tight. I've seen people report on getting massive corrections and knock from a loose spark plug.
 

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Discussion Starter · #6 ·
I've checked all gaps at .027. Plugs are only 4.5k kms old and I checked them at 3k. Even replaced my problem cylinder coil pack thinking it would cause it (I broke it actually but maybe thought it would fix).
 

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I am sure you realize this but seemingly being isolated to cylinder three automatically eliminates a bunch of possible candidates:

fuel quality, air quality, air temperature, etc. Leads me to suspect something mechanical like spark plug, or injectors?

But I keep my mechanical knowledge fairly limited so thats about as much advice I can muster up. Whether its good advice or not is even questionable.
 

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Based on the fact you said that the RMM fixed it for awhile id say you are getting a false knock reading.
 
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Discussion Starter · #9 ·
Yeah it's only cylinder 3. My OAR is perfect at -1 and my AFR is at 14.70. I've replaced the coil pack as I've said and I checked the spark plug and it's fine. My next thing I'm going to do is see if anything is hitting the block. It's funny, when I start in 2nd, it doesn't do it. It's only in 1st.
 

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Based on the fact you said that the RMM fixed it for awhile id say you are getting a false knock reading.
I'm with Tyler if it's ONLY happening in that one cylinder.
 

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Discussion Starter · #11 ·
Yeah it is. 1st and 4th are fine. Not a single negative reading what so ever. 2nd will get the occasional -0.25 to -1.00.
 

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Yeah it is. 1st and 4th are fine. Not a single negative reading what so ever. 2nd will get the occasional -0.25 to -1.00.
Ever find a solution for this?

I'm getting negative corrections in the -4s in cylinder 3 only. Others are normal. Happens in first gear and seems to happen most often accelerating into a left hand corner from stopped.

I have NGK one step colder plugs that I installed a couple weeks back gapped to .026. I guess tomorrow I can pull the plug and inspect it and reinstall. Any thoughts?

By the way is cylinder 3 the second one in from the drivers side?
 
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