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I’m at a loss please help me figure this out

PunkST

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#1
Mods on the car are as follows
VTsnorkel
Drop in filter
Mishimoto silicon tune
Stock crossover pipe
Stock turbo
Stock wastegate
Stock Cat/ DP
Mountune RMM
Cobb AP stage 3 91 octane tune
Step colder plugs
Stock hotside pipe
MAP intercooler
CP-E coldside pipe with HKS bov
Symposer delete


The issue I’m having is intermittent as hell and very very frustrating
While driving in rain for over 45 minutes to an hour. If I have to stop the re accelerate, or make a turn and re accelerate with anything other than baby light pressure the car stumbles and fall on its face for a second or more like it’s drowning in fuel or the ignition timing is all wrong. Then it goes away and doesn’t come back.

I have nothing out of what seems normal for my car showing on my AP
No misfires registered by the car, no check engine lights. And no traction control light. (I know what tcs interference feels like and this isn’t it.

When this first happened mid summer I thought it was just bad gas. A month later it’s back. So it can’t be that
I swapped intake stuff other than the snorkel away from my Cobb intake to current setup listed. So that rules that out as a culprit because it’s done it on both now.

Like I said I’m at a loss. I can’t afford to just toss money at it. And I have to work within the tune files I have, so a custom tune is out of the question.

Anyways please help, I’d like to keep this car and keep modding vehicles. And tuning them. But if this is what the result is with changing engine mapping it’s very discouraging and makes me want to return the car to stock and trade it in for something else and not a ford.
 


TyphoonFiST

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When does this happen? Right after you get gas? I'LL put money on it that it is fuel related. These days bad gas is as few and far between as seeing an actual Unicorn. How many miles on the car? What level is your fuel at when this happens? The more info the better buddy.....[raceflag]
 


OP
PunkST

PunkST

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Car has 67k. Doesn’t matter fuel level or when I’ve gotten gas. First time late July early August I had 3/4 tank and mid trip in muggy humid weather.

Happened today at 1/4 tank in rainy cold weather.
 


Quisp

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#4
Maybe try cleaning and checking map sensor and throttle body connections. Maybe slather some dielectric grease, but modern connectors are pretty weather resistant.
 


zanethan

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#5
Mine has had this happen twice. Unsure what it is either. It only happens when it’s raining. It hasn’t happened since I’ve tuned it but it was also 6+ months between occurrences previously. I agree it feels like a fuel issue of some kind.
 


Ford ST

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It happened to my brand new 2017 when driving in the rain for a very long time. I needed to make a U-turn I was pissed off because I was lost and I got on the car and it stumbled on its face it popped, crackled, hesitated. With that said I think you're perfectly fine there's obviously some type of issue that causes this. If it only happens when driving in the rain for extended periods of time I think you're blowing this out of proportion. I'm different little problems don't really bother me. The only intake modification that I have is the ST200 airbox. I believe it may have to do with the intake collecting moisture it's slowly continues to build up as you drive, and when you come to a stop and get back on the car it eats the water. Let's say this is true that snorkel would only add to that problem of it inhaling water moisture. Honestly I believe that's what it is. Moisture buildup in the intake system.

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OP
PunkST

PunkST

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Thread Starter #7
I’m going to try that. I moved down to the stage 2 map just to see if it’s tune related, Still rainy here but my trip to work might not be long enough for Things to get properly wet.

Another thought is how long do stock coils last on this car?
 


zanethan

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#8
In my experience, coil-over-plug ignition systems like ours SHOULD last about the life of the car. They are usually a pricey item to replace, so I'd rule out everything ELSE first.
Ohh they’re pricey alright. I stupidly broke the tiny little tab for the clip and it was $50 per coil on rock auto. Thank god I only broke one tab.
 


OP
PunkST

PunkST

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Thread Starter #9
I’m on step colder ngk 6510s. They currently have 11k miles. I’m not ruling anything out as a possibility. It should last. But most folks don’t have 67k on the car in 2.5 years of ownership. Lol. I’m gonna attack what I can with dielectric grease. Maybe it’s just a wet connection somewheres.
 


TyphoonFiST

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I’m on step colder ngk 6510s. They currently have 11k miles. I’m not ruling anything out as a possibility. It should last. But most folks don’t have 67k on the car in 2.5 years of ownership. Lol. I’m gonna attack what I can with dielectric grease. Maybe it’s just a wet connection somewheres.
Dielectric grease for what? Do you know why it's used with spark plugs?



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PunkST

PunkST

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Thread Starter #11
Dielectric grease on connectors to keep moisture out.
 


TyphoonFiST

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Dielectric grease on connectors to keep moisture out.
Its main purpose is so that the Coil plug boots/Spark plug boots don't stick to the porcelain due to the heat generated by the spark plug and the engine itself in turn tearing the boot upon removal. The moisture issue is secondary and I have never seen it as an issue on engines of all sorts. Now if you like to fancy a power washer on your engine to keep it clean I can see that.... but there are so many design features built into electrical components now its quite fascinating its not really needed in most cases.....Di-electric grease is also a killer/stopper of electricity....hence the word Di- before electric....I've seen people aggressively use it and wonder why their car runs funny....after cleaning gobs of it out of the Spark plug boots the car runs fine again. They do make conductive grease though if you can find it.[thumb]
 


OP
PunkST

PunkST

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Thread Starter #13
I’ll go at it sparingly. I do clean my engine bay like twice a year. Other than those 2 events ( just gunk and a garden hose) I use quick detailer and a rag.
 


OP
PunkST

PunkST

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Thread Starter #14
^same with the shooting in the dark. I haven’t gotten it to hiccup again. Only thing I have changed is dropping down to the stage 2 91 octane OTS Cobb tune.
 


OP
PunkST

PunkST

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Thread Starter #15
Bumping this.
Back on fresh stock heat range. Still did it. I’ve found a possible culprit besides bad coils. I have a bit of bare wire on the harness going to my IAT sensor. Looks like a trip to ford to pick up a pigtail for that in my near future. After that, if it still does it. I’m thinking coils.
 




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