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Ignition Timing Cylinder bouncing + & -

Spears2nd

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Pittsburgh, PA, USA
#1
My 17 Ford Fiesta ST ignition timing on cylinder 4 was bouncing from positive to negative. I know positive corrections are really much of a concern, but it’s also going into the negative as well lowest I seen so far is -9.50 & reaching positives up to 40.0.
I need help determining if it’s fixable or if I’m gonna need a engine. I listed modification below if that’d help. I will upload data-logs when I access my computer.
Modifications:
Cobb Accessport
Mountune Highflow Filter
Cobb RMM
3” Cat-Back Exhaust
 

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Clint Beastwood

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#4
You need to flash the stage 0 maps and see what happens, the stage 0 is basically a stock map with logging enabled. If it's still doing it, grab some datalogs and upload them to datazap.me

With corrections that extreme but the car not being currently explode-y, it might just be a false-knock, like a loose knock sensor or head shield. Isolate by removing variables, the first of which being, don't run whatever tune you are running.
 
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San Juan
#7
My 17 Ford Fiesta ST ignition timing on cylinder 4 was bouncing from positive to negative. I know positive corrections are really much of a concern, but it’s also going into the negative as well lowest I seen so far is -9.50 & reaching positives up to 40.0.
I need help determining if it’s fixable or if I’m gonna need a engine. I listed modification below if that’d help. I will upload data-logs when I access my computer.
Modifications:
Cobb Accessport
Mountune Highflow Filter
Cobb RMM
3” Cat-Back Exhaust
It's perfectly normal on a variable timing engine for that to happen. It is not the corrections. You should be looking at knock rather than Timing.
 
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Location
San Juan
#9
So comes the question when it comes to ign. corrections...What is acceptable? what range?
I'd say it depends on the tuner, I've seen knock appear and the Ign Correction still be positive. Also some tunes leave just 1.00 correction in positive and it doesn't go above that. Also seen the ones that leave it like OTS tunes of having 6.00 being the highest.
 

pwnall1337

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#10
Before you get freaked out, ignition timing is the final timing calculation of that cylinder and this is NOT ignition corrections. You should realistically not be monitoring timing and should only be monitoring ignition corrections. It's normal for timing to flux between -20 (low rpm high load) and +40-70 (low rpm low load). The borderline tables are multiplied against OAR and blend with MBT to create a final timing calculation.

OAR should be -1 after a few wot pulls on most tunes (our tunes default to -1 on reflash)

I would not be concerned about ignition corrections unless you have a high occurrence of corrections worse than -1.50 (ex: -1.75) at wide open throttle (not min/max readings) as at that point the tuner may need to address the tune, however when you tune a lot of cars you can tell if it's the tune or the car. I can usually tell pretty quickly if you have bad plugs or too large of a plug gap when I keep consistent timing across multiple customer vehicles and only 1 vehicle exhibits issues.
 
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