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Backfiring after Stage 1 install

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Old Apr 26, 2023 | 06:57 PM
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Default Backfiring after Stage 1 install
Did a full stage one on my ‘22 SG 107 with TBR 2-1 exhaust, SE air cleaner and PV4 tuner but on startup and when giving throttle I’m getting heavy back fire through the air cleaner and just started with a random sucking sound. Sprayed for air leaks using WD-40 on manifolds and no change. Did replace spark plugs before start up…Also, no codes come up when scanned…Any clues?? I’m stumped. TIA
 
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Old Apr 26, 2023 | 07:10 PM
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i would start with reflashing the tune, very odd to get an early spark backfire thru the intake. timing is off or tune may be corrupt.

retune to stock and see if it clears up, then reload and reflash the tune
 
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Old Apr 26, 2023 | 07:13 PM
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check them new plugs
 
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Old Apr 26, 2023 | 07:22 PM
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Originally Posted by stormin08
i would start with reflashing the tune, very odd to get an early spark backfire thru the intake. timing is off or tune may be corrupt.

retune to stock and see if it clears up, then reload and reflash the tune
Retuned to stock tune let it idle for a bit had the back fire still, re-flashed with tune from fuel moto and pre-Installed tune on PV4 still get the same results. Throttle is a bit more responsive but still have back fire on initial throttle and heavy air suck sound on initial throttle.
 
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Old Apr 26, 2023 | 07:24 PM
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Originally Posted by NZLowrider
check them new plugs
Double checked all plugs for spark and all came back good with plenty of spark.
 
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Old Apr 26, 2023 | 09:17 PM
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Did you install the Ventilator air cleaner? Did you remove this bracket? If not, you likely cracked your throttle body.


 
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Old Apr 26, 2023 | 09:20 PM
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Originally Posted by 702
Did you install the Ventilator air cleaner? Did you remove this bracket? If not, you likely cracked your throttle body.

That was the first thing I took after the stock filter and housing came off.
 
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Old Apr 26, 2023 | 09:23 PM
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Originally Posted by Javier_107
That was the first thing I took after the stock filter and housing came off.
If you've installed everything correctly and didn't break any plug wires, I would suspect the tune.
 
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Old Apr 26, 2023 | 09:23 PM
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Originally Posted by Javier_107
Did a full stage one on my ‘22 SG 107 with TBR 2-1 exhaust, SE air cleaner and PV4 tuner but on startup and when giving throttle I’m getting heavy back fire through the air cleaner and just started with a random sucking sound. Sprayed for air leaks using WD-40 on manifolds and no change. Did replace spark plugs before start up…Also, no codes come up when scanned…Any clues?? I’m stumped. TIA
Originally Posted by stormin08
i would start with reflashing the tune, very odd to get an early spark backfire thru the intake. timing is off or tune may be corrupt.

retune to stock and see if it clears up, then reload and reflash the tune
Originally Posted by NZLowrider
check them new plugs
Originally Posted by 702
Did you install the Ventilator air cleaner? Did you remove this bracket? If not, you likely cracked your throttle body.

This is how it’s idling
 
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Old Apr 26, 2023 | 09:26 PM
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Originally Posted by 702
If you've installed everything correctly and didn't break any plug wires, I would suspect the tune.
Thats where I’m leaning also. Only way to go is a dyno tune or reach out to fuel moto see if they have any other suggestions for the tune.
 
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