Built engine high RPM hesitatiom

[STE92]

Just recently completed breaking in my engine and started the tuning process. Having a weird issue at high rpm, bank 1 AFR goes lean 20, car hesitates for a second and continues. I was thinking hpfp going bad, fuel pressure deeps for a second and recovers doesn't affect bank 2. I get no codes, any help will highly be appreciated? I'm running on fumes

N54
Closed deck block
JE pistons 10.5.1
Molnar rods
Arp bolts/head studs
Maximum psi hub/vtt bolt catch

P&P head
Supertech valve train
Shrick LL cams

DocRace kit GTx4088r
DocRace IM 750cc inj/index 12 inj
PR stage 3 full E85
Vtt shotgun
Vtt dual catch can
Jb4/mhd (v8bait)

Additional information

Firmware	Interface	Engine	TMAP_V	AvgIgn	DWP	MethTriggerMode	FF	MethSafeMode	MethAdd	MethScale	MethPSI	VIN	E85_Setup	VFF_Offset	fuel_30	fuel_35	fuel_40	fuel_45	fuel_50	fuel_55	fuel_60	fuel_65	fuel_70
30/139//2	JB4 Android A330	E Series - N54	1.96	22.1	24	0	18	0	0	99	0.0	............	NONE	132	50	50	50	50	50	50	50	50	50

BoostSafety	PID Gain	AutoShiftRed	Fuel_OL	FUA	1st_limiter	2nd_limiter	3rd_limiter	Options	N20_TMAP	6CylMode	LastSafety	duty_15	duty_20	duty_25	duty_30	duty_35	duty_40	duty_45	duty_50	duty_55	duty_60	duty_65	duty_70
26.0	25	0	0	0	0.0	0.0	0.0	NONE	1	4	1	50	50	50	50	50	50	50	50	50	50	50	50

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[GreyNBlueE92]

I vote O2 sensor, I had a bad O2 that would intermittently go to 20 then eventually stayed there until replaced.

 

[STE92]

I vote O2 sensor, I had a bad O2 that would intermittently go to 20 then eventually stayed there until replaced.

I think so too

 

[silverstreak18]

Sounds like a cooked oxygen sensor. Thats what they'll do when they've been overheated.

 

[Milan]

Sounds like a cooked oxygen sensor. Thats what they'll do when they've been overheated.

Agreed

 

[STE92]

Replaced sensor...no change

 

[GreyNBlueE92]

Try and reset adaptations, possibly more than once... Maybe try an O2 spacer... Just ideas based on what I've read. Good luck

 

[STE92]

I'll try using INPA instead of MHD

 

[silverstreak18]

Swap Bank 1 & 2 sensors just to be absolutely sure. Then I would go from there.

 

[STE92]

Already did...issue persist

 

[doublespaces]

@STE92 I've uploaded your log to the datalogs section and embedded it.

 

[NoGuru]

Might have an injector not spraying or over-spraying.

 

[STE92]

Might have an injector not spraying or over-spraying.

Injectors were swapped with no changes

 

[STE92]

I'm at a lost right now

 

[Slowagon54]

Hi,

double check the spark plugs. Maybe one is loose.

I'm at a lost right now

 

[STE92]

Hi,

double check the spark plugs. Maybe one is loose.

Has new plugs gapped .018, torque to spec, reset adaptations with INPA, went back to stock coils from BL, moved my o2a...make sure woring wasnt close anything electrical. NO Change. Really running out of options here

 

[Slowagon54]

Has new plugs gapped .018, torque to spec, reset adaptations with INPA, went back to stock coils from BL, moved my o2a...make sure woring wasnt close anything electrical. NO Change. Really running out of options here

I am sure you have discussed the issue with Justin. What is he saying?

Timing for 3 goes flat for quite a time. It should go up again, but it does not really. Trims for Bank 1 is off as well. So you may have a closer look at cyl 3.

 

[Slowagon54]

Have you been able to solve the issue?

 

[STE92]

So Justin, thought that maybe I was looking at some kind o2 wiring issue. I decided to remove the IM to inspect the junction box and the o2 wiring under the IM. I found that my O rings/manifold gaskets looked flat and u can see trace mark of the areas were it was leaking un-metered air into the cyl not sealing. I ordered new ones coming in today, I also inspected wiring make sure there are no issue there. Will report back with results.

 

[Slowagon54]

Makes sense. Thats why i asked to check the plugs. I had a few loose and got plenty of corrections and lean condition. Took me some time to sort it out...