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Hi guys,
Yesterday I got my final tune map from the tuner. I tested all the maps and uprev features for a bit and everything worked. I went to do a pull in 2nd gear at about 45mph in the pop map, and my car began to stutter and I believe it was misfiring.
It's sounds a bit like a subaru and really isn't acting right.
I thought the tune may how fouled a plug, so I took all my plugs out and cleaned them off, re-gapped, and sanded them clean. All the plugs were at about 0.055 after about 20k miles. I put the plugs back in and and reassembled everything and the car acted fine up until it was warm, and then it began to sputter a bit again. Not as much, but in high load situations like low rpm and more than ~40% throttle the car breaks up. Also at idle after driving for a bit.
One of my coil boots was a bit malformed, making the bottom tip of it taper slightly on one side. Could this be the issue? I ordered a new one anyways, with the thought that it could be arcing or something.
This all happened about 10-15 minutes after driving around on all maps just fine, mostly in the pop map.
Has anybody here ever had this issue or a similar one after or without a tune? Any ideas?
Definitely sounds like the coil pack is bad, I would replace all the plugs again just to rule them out as well.
ANY kind of damage on the coil pack and you should replace it, especially on the secondary side of the winding, it takes a lot of very perfect insulation to contain the 35,000 or so volts being generated.
Definitely sounds like the coil pack is bad, I would replace all the plugs again just to rule them out as well.
ANY kind of damage on the coil pack and you should replace it, especially on the secondary side of the winding, it takes a lot of very perfect insulation to contain the 35,000 or so volts being generated.
Thank you cleric! Do you think I should try out the new coil boot before replacing the whole coil pack?
On another note: I had a guy in a forum say that NGK plugs should never need to be regapped, but all of mine were at ~0.055 instead of the 0.044 they're supposed to be at. Do you think something else could be making them wear quicker/have a larger gap? I should just replace them all, you think?
Another guy told me that now that I've gapped the plugs, there's going to be pieces of spark plug iridium in my combustion chamber. Do you know if this is a thing?
Last edited by MitchJDeP; May 9, 2020 at 10:41 PM.
About the spark plugs, you can't use the traditional "spark plug gap wheel tool". That tool is designed to wedge between the electrode (middle part) and ground strap (hook part) and you physically pry the gap bigger. Platinum and iridium plugs have an EXTREMELY small/fragile/weak electrode and you cannot pry on that piece or you will bend it.
That tool was designed to work primarily with copper plugs that have a very large and solid electrode, however you can still use the wheel gap tool as a MEASUREMENT device. In order to open/close the ground strap you need to manipulate ONLY the ground strap, they make a tool that's designed specifically for that as well, it's typically used when you are using feeler gauges as the measurement device.
So yes you can definitely re-gap platinum or iridium plugs, but you cannot pry on the center electrode.
Here are a couple picture examples of the two main types of tool for opening the gap, to close it you just face the spark plug with the ground strap down on a bench or something solid and gently PUSH the gap closed, then open it up to the measured amount, it's very easy to close the gap too far so you always want to OPEN the spark plug gap to the correct measurement since that's easier to be very accurate with the tool.
As for regapping the spark plugs, you should definitely set them at factory gap, no question. Buy the tool to regap them properly or buy new plugs. The gap will open on it's own over time as the plugs age because metal on the electrode is actually blasted off at the atomic level due to the nature of combustion, YOU ARE GETTING IRIDIUM IN THE COMBUSTION CHAMBER and this is completely normal. What that other guy probably meant is that you could easily break off (weaken enough so it snaps off when installed) that small iridium tip with a typical circle/wheel spark plug gap tool.
As for the coil pack, I honest to god didn't know the boot could be removed and replaced as an separate piece lol. You learn new things every day!
However, the damage was probably caused due to overheat on the contact spring so I would just replace the entire coil pack, there might be something else going on internally. Something caused the damage and it wasn't heat soaking out of the valve cover.
