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Cold Weather 40-50° One Step Colder, Misfire?

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WICHITA
#1
Anyone elses car misfiring with colder weather and having One Step Colder spark plugs?

I've started to notice my car started to misfire under hard acceleration after 4ishK rpm. Only ups I have is Knock off Mishimoto Intercooler, NGK One Step Colder, Hot Side Intercooler pipe. Pedal Spacer, BOV 50/50 adapter, K&N drop in, Ram Air Induction hose, Mountune Symposer Delete and 88A AWR RMM.

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Business6

Senior Member
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#2
I haven't noticed anything unusual but I also don't have an AP to monitor it. Temps are going to drop a fair bit more tonight/tomorrow into the mid 20s so yeeeee
 


OP
purityracer316
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Thread Starter #3
hooked up the snap on scanner at the shop I work at and was getting a cylinder 4 misfire. Swapped that plug into cylinder 1 and the coil to cylinder 2. It followed the plug so got another spark plug and started running better. Then started doing it again with barely 100 miles on it.

I've been reading around that one step colder tends to foul out faster depending how you drive your car. Me I have a 4 mile commute to work with stop lights for each mile. So I don't really get on it because my oil temp by the time I reach work is about 100°. When I do drive my car it's still no more than probably 6 miles at a time because everything is within range of where I live. Even where I have to get E85 for the e30 tune is a short distance. I'll just warranty out the ngk one step colder and keep them in my toolbox and just go back to factory.

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OP
purityracer316
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Thread Starter #4
[MENTION=10267]purityracer316[/MENTION] You have a similar commute to mine - I estimate I'm going to be putting about 4,500mi/yr on my FiST at most ever since I've moved closer to work.

Do you let the car warm up before you start rolling? At the very least let it idle for a few minutes or until the temp gauge has 3 or 4 bars on it before you shift into gear when ambient temps are below 50F, and let it idle until the revs drop to =<1,000rpm during warm weather so that you can be assured the oil is circulating and the engine is ready for load. And, yes, colder plugs can foul more easily because they don't get hot enough to "burn off" deposits as easily or quickly as hotter plugs do. Short commutes will exacerbate this issue, especially on a stock engine. With your mods and driving habits, you shouldn't need colder plugs anyway.
Yeah I let it warm up. I normally wait until my oil temp hits 120° until I actually start getting it into the higher boost range.

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OP
purityracer316
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WICHITA
Thread Starter #5
Went back with the OE Motorcraft SP-532. Running so much better. Thought cold weather was an issue but it was just the commute driving and the way I drive that was fouling out the NGK 6510 one step colder spark plugs. I've been able to get on it with no worries of it misfiring anymore.

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Business6

Senior Member
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#6
Went back with the OE Motorcraft SP-532. Running so much better. Thought cold weather was an issue but it was just the commute driving and the way I drive that was fouling out the NGK 6510 one step colder spark plugs. I've been able to get on it with no worries of it misfiring anymore.

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I just put Motorcraft 532 back in as well. Idle seems better on a cold start but I haven't driven it just yet.
 


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