Spark Plug Gap
Asked by dannnyjos Dec 11, 2017 at 11:15 AM about the 2012 Nissan Altima 2.5 S
Question type: Maintenance & Repair
I recently bought original spark plugs (NGK) for my 2012 altima and they were supposed to be gapped at
the factory at 0.044. However, when I installed them I noticed that the car was rough idling and the engine
was noisier than normal. I decided to check the gap and they were actually gapped at 0.041-42. I
corrected the gap to 0.044 and the engine is running better. I then decided to run a little experiment and set
the gap at 0.050 and the engine is even quieter.
My question: would increasing the gap even more (like to 0.055) have any detrimental effects on the car
(ignition system, coils, etc.)?
Thanks.
6 Answers
Thanks for your response TennisShoes... I'm running stock Nissan coils, but I got new Denso cables. Do you think that the coils might be damaged by running hotter, and if so, are there signs that they're going bad? I ask because I do not have any professional measuring equipment to accurately test the coils. Initially I increased the gap from the original 0.044 to 0.050 and the car's engine felt quieter and more powerful. Last week I increased it yet again to 0.055 and didn't see any power gains. However, the engine feels even more quiet than with 0.050. I personally love it (the smoother the better for me) but I'm concerning that the ignition system is being overtaxed and I have no way of telling.
"If the demand is almost the same as the coil output then they can't handle that wide of a gap" Did you mean to say "they can handle that wide of a gap" ??? Ok, that's an interesting idea: instead of measuring the temperature, just measure the KV output. However, being the untrained car person I am, I do have a a few questions: - What should I tell the shop mechanic to do once I take the car there? - How do I know what the normal KV output range should be for my coils? - When you say a "scope", what type of device are you referring to exactly? Thanks.
OK, thanks for the info TennisHoes. So, what is a "scope" again?
TennisShoes NP, your input was very informative.
ideally when to replace spark plugs? my car is now 110000 miles done 2012 altima
ponchohunter answered 10 months ago
My NGK's came set from NGK @ 0.40/hair under . It needed to be .044. I put them in because Nissan OEM Denso's was set @ 0.40 and fouled greatly. NOPE! Has to pull them and reset. BIG difference! Lets hope that and MAF, new air filter, new spark plugs knocks out the p0171. Car runs good. It was choppy in deceleration before. Not as bad now..... Get my MAF sensor tomorrow.