Official OpenFlash Tablet FA20 Tuning Tech Discussion Thread

[steve99]

Originally Posted by lucid215

just flashed my 13 limited brz with the stage 1 rom. drove the car easy for a few miles to get the car to learn a bit. gave it a good 3rd gear pull and the power is very smooth. it may just be me or the car hasnt fully learned but it doesnt seem like the vvl doesnt kick in as hard. ill try to get some logs today. what exacly needs to be logged? thanks

you have aftermarket intake from memory ?

These can upset MAF scaling and cause high fuel trims.

If you fuel trims were low their is little to learn

Log

STFT
LTFT
FBKC (Knock correction)
IAM
FLKC
RPM
MAF V
Engine load
throttle position
IAT
AFR
Commanded AFR

[evox2frs]

Switched to E85 for the first time today. Followed the exact procedure @steve99 has in his thread. Drove 30 miles easy, then started testing WOT. Everything felt ok (coming from 1.34 91oct), but my LTFT at WOT is 11.73. At idle, LTFT is 3.5%. Mods in sig. Had my fiancé watching the OFT, and she said my AFR at WOT looked right, tapering to 11.8 at 7k rpms. We continued down a back road pushing it with no issues.


Then, I turned on my AC as we went through town slowly. Car started acting crazy, and threw a U0073 code, and went into limp mode. Pulled over right away to clear it. Now, am paranoid with a full tank of E85. Given the information I provided, should I even risk capturing a WOT log? Thanks for any input

[Terrapin77]

Originally Posted by evox2frs

Switched to E85 for the first time today. Followed the exact procedure @steve99 has in his thread. Drove 30 miles easy, then started testing WOT. Everything felt ok (coming from 1.34 91oct), but my LTFT at WOT is 11.73. At idle, LTFT is 3.5%. Mods in sig. Had my fiancé watching the OFT, and she said my AFR at WOT looked right, tapering to 11.8 at 7k rpms. We continued down a back road pushing it with no issues.


Then, I turned on my AC as we went through town slowly. Car started acting crazy, and threw a U0073 code, and went into limp mode. Pulled over right away to clear it. Now, am paranoid with a full tank of E85. Given the information I provided, should I even risk capturing a WOT log? Thanks for any input

U codes are nothing to worry about. You probably plugged in the OFT after starting the car.

[evox2frs]

Originally Posted by Terrapin77

U codes are nothing to worry about. You probably plugged in the OFT after starting the car.

Yeah, I kept trying to rig mount the OFT on the dash, and it lost communication a couple of times. After some research, I see that code is related to that, appreciate the confirm.


The car definitely pulls harder top end. Running 3rd-5th has never felt like this. I miss the v1.34 Stage 1 kick at 4k rpms though. I want to go out and make some logs, but nervous about the LTFT's at this point. 11.96% at WOT doesn't sound good, right?? I saw Shiv post a dyno with OFT and TRD intake and all was good and made over 200whp. I don't want to have to scale my maf if I don't have to.

[steve99]

Agree with above post U0073 is loss of contact with Body control module. possibly hangover from when you flashed or as a result of data traffic on buss due OFT monitoring.

Their are 4 bands of air flow rates where ECU stores learned long term fuel trim. so the LTFT will changes as RPM hence Air flow changes across rpm /flow rate ranges.

If the AFR is 11.8 at WOT that seems ok , actually on the rich side.

It sometimes takes a while for the ECU to "learn" the higher end as it only learns on Closed loop mode ie steady throttle, and most people don't go steady throttle over 4000rpm they just nail it. So to set those trims quicker drive in second or third at partial steady throttle and hold rpm around 3500-4500 up a slight incline is useful.

If you want to scale MAF your going to need to go back to petrol as the fuel trims will vary widely due varying ethanol content of E85.

[evox2frs]

Man, you are extremely helpful on this forum, thanks @steve99. I'll take your advise on all measures, and see how she's running with some more miles on the tune.

[steve99]

Originally Posted by evox2frs

Man, you are extremely helpful on this forum, thanks @steve99. I'll take your advise on all measures, and see how she's running with some more miles on the tune.

Thanks,

The first tank of "e85" will always have the left over petrol mixed in so LTFT trims can be a bit further "off" then usual.

[OmarYasin]

@steve99 last week as I pulled up to 5k in first gear I got a cel p0465?? Ithas something to do with fuel level sensor circuit high? I erased the code filled e85, I was at 1 quarter of the tank and no codes sense then, I have been data logging I might have a exhaust leak so im getting all new gaskets first off with header and overpipe, u think it was some bug in the system or something to worry about??

[steve99]

Originally Posted by OmarYasin

@steve99 last week as I pulled up to 5k in first gear I got a cel p0465?? Ithas something to do with fuel level sensor circuit high? I erased the code filled e85, I was at 1 quarter of the tank and no codes sense then, I have been data logging I might have a exhaust leak so im getting all new gaskets first off with header and overpipe, u think it was some bug in the system or something to worry about??

Think that code is EVAP purge problem, can be vacuum leak hoses related to fuel tank, check fuel cap is tight and any hoses that go the purge canister are connected and tight. You have not had intake manifold off for BPB install ?? their are a couple of hoses around their will no clamps from memory. Boosted guys need to install clamps so they don't leak or dislodge.

don't think that code will be caused by exhaust gasket leak.

[OmarYasin]

Originally Posted by steve99

Think that code is EVAP purge problem, can be vacuum leak hoses related to fuel tank, check fuel cap is tight and any hoses that go the purge canister are connected and tight. You have not had intake manifold off for BPB install ?? their are a couple of hoses around their will no clamps from memory. Boosted guys need to install clamps so they don't leak or dislodge.

don't think that code will be caused by exhaust gasket leak.

U know , I thought the same thing, when I filled up, the cap came off with no real effort.... no codes sense then.. I dont have bpb, bpb its not recommended with e85 right? Theres no tune for both blocks and e85

[steve99]

Originally Posted by OmarYasin

U know , I thought the same thing, when I filled up, the cap came off with no real effort.... no codes sense then.. I dont have bpb, bpb its not recommended with e85 right? Theres no tune for both blocks and e85

Yes loose fuel cap can cause that code

Yes Shiv said E85 and BPB were not a good mix, BPB shifted peak power lower in rpm range but E85 did its best work at a higher RPM than where BPB were efficient so it was counter-productive.

[OmarYasin]

Yeahh good thing I didnt buy it a month ago like I planned too.

[OmarYasin]

The code I pulled was a p0463, wrote it down just found it @steve99

[steve99]

Originally Posted by OmarYasin

The code I pulled was a p0463, wrote it down just found it @steve99

yes that one is fuel level sensor problem may cause fuel gauge to be inaccurate, probably a trip to dealer if that returns,