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Breaking up while I’m fully throttle

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Location
New york
#1
So I have a fair amount of mods done. But my car just recently started breaking up if I do a WOT log. Only when I start from lower RPMs though. Any one have any ideas or similar issues?? Thanks
 


SrsBsns

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San Diego
#2
What do you mean, "breaking up?"

What mods do you have done? Are you datalogging?
 


OP
Sean32
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New york
Thread Starter #3
It like sputters and cuts power in and out. I have an intake, catless dp, full exhaust, turbo smart bov, and ngk one step colder plugs. And I’m currently being custom tuned by Dizzy tuning


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Messages
405
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122
Location
Chino Hills
#5
How many miles are on the step colder plugs? How far do you drive on a daily basis since you installed the plugs? Is the sputtering/breaking up happening in other gears besides 6th gear?

If you answer in this order:

More than 8k miles

Less than 10 miles daily

Does not happen in 6th gear, but all others

Then check your spark plugs for fouling or coated with dark carbon build up. Most likely the two closest plugs to the driver side will have nasty build-up.
 


Last edited:

CSM

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Cleveland, OH, USA
#6
How many miles are on the step colder plugs? How far do you drive on a daily basis since you installed the plugs? Is the sputtering/breaking up happening in other gears besides 6th gear?

If you answer in this order:

More than 8k miles

Less than 10 miles daily

Does not happen in 6th gear, but all others

Then check your spark plugs for fouling or coated with dark carbon build up. Most likely the two closest plugs to the driver side will have nasty build-up.
Sounds a bit like plugs to me too. I was at a dyno day once and a local FiST was stuttering under WOT at higher RPMs. Swapped in fresh plugs with proper gap and issue went away
 


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405
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Location
Chino Hills
#7
Exact same thing happened to me a month ago while data logging. It was breaking up in the low-mid range during wot. Forgot to change my soak plugs after 10k miles.

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Location
Bristow
#8
Yeah my car started sputtering under WOT the last two weeks. 2 months before it started I switched to iridium spark plugs (1 step colder). I checked all my battery connections and I changed the plugs back to OEM ones but the sill issue is still happening. If anyone has any pointers they’d be greatly appreciated I’m completely stumped atm
 


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19
Location
Bristow
#10
Yeah my car started sputtering under WOT the last two weeks. 2 months before it started I switched to iridium spark plugs (1 step colder). I checked all my battery connections and I changed the plugs back to OEM ones but the sill issue is still happening. If anyone has any pointers they’d be greatly appreciated I’m completely stumped atm
New coil packs came in and the sputtering issue was resolved :)
 


HBEcoBeaST

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Huntington Beach
#11
What's funny is everyone I know with spark plug/coil pack issues is running colder plugs. I have run OEM and 1 step colder on a E30 tune by stratified. The colder plugs started looking bad about 10k in and the OEM plugs at 50k (20k tuned E30) looked in great shape

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Location
Bristow
#12
Believe it or not I actually changed the plugs back to OEM from 1 step colder plugs gapped to .027 and the colder plugs were significantly more dark due to carbon build up. I think I will be running the stock plugs until I can go get another set of them.
 


TyphoonFiST

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Rich-fizzield
#13
So what were you seeing for data on the ap3? negative corrections? what cylinders seemed to have the issue? Was there a check engine light? Did you ohm out the Coils to see what they were at? Does anyone know the spec for doing that?
 


Messages
60
Likes
19
Location
Bristow
#14
So what were you seeing for data on the ap3? negative corrections? what cylinders seemed to have the issue? Was there a check engine light? Did you ohm out the Coils to see what they were at? Does anyone know the spec for doing that?
Unfortunately I just didn’t drive the car once it started breaking up. The only time I drove it after it started breaking up was when I was swapping out parts. Maybe the post starter has his log.
 


Clint Beastwood

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Laguna beach
#15
Anyone know if stock coils from any other ford cars count as "upgrades" for the FiST? When I had my Abarth and upgraded the coils on my wife's alfa for a remap, the stock Alfa coils were a drop-in upgrade for the Abarth that made a huge difference. Direct fit!
 




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