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Discussion Starter #1 (Edited)
Hello everyone,

Looking for some advice here.. got my car rebuilt recently at Outfront Motorsports in Buena Park, CA with a stock shortblock assembly.

It's got a few bolt-on parts which needed a basemap for break-in procedure.

The tuner is Ron from Phatbotti Tuning in Anaheim, CA. He's instructed me to take a datalog to review the engine's state. He states that the car has a vacuum leak or a fueling issue which is leaning out the motor, having too much +AF correction %.

Since then, the car's had a smoke-test with no visible leaks and a fuel pressure test which read nominal. Outfront believes the car is fine?:confused:

Only thing I can think of is a bad throttle body or MAF sensor? I remember hearing ticking noises while cleaning the throttle body and gave it a shake. Should I start by replacing the throttle body?

For those of you who are more aware of the tuning side, what do you think of the map and datalog? Link attached!:tup:

*Parts list for power:
-Catless bell-mouth downpipe + cbe
-Cobb EBCS
-Cobb AP V3
-Perrin Turbo inlet (2.4" stock size) + elbow piece for intake box.
-Stock rebuilt turbo
-Grimmspeed AOS (which isn't known to be an issue in this case..?)

Thank you!

basemap and datalog
 

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yamahaSHO would know better than i, but i think you want your AFR in the ~11 range.. On my 07, AFR flatlined at 11.01 and with my 2017 flatlines at 11.03 with the cobb stage 2 OTS.
 

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I agree but I don't think there's any evidence he is lean. And actually re-reading the original post he's only concerned with closed loop operations and STFT and LTFT. Anyway your approach is certainly safer if the driver has no feedback on A/F during the pull.

Eh, if you suspect being lean, I'd start with a good 2nd gear log... You're far less likely to have issues if the motor is running improperly.
 

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Discussion Starter #8
A throttle body does not lean out the air:fuel mixture. Where did you connect for you boost leak test?

Outfront Motorsports said they connected into some of the vacuum lines leading off the turbo inlet and a couple of other places i don't recall specifically.. they said no signs with a smoke test. Fuel pressure test came back nominal as well.

I can view the logs on my phone, but I will look later on a computer.
Thanks!

Just offhand it's not a very good data set. You never got WOT, you have a very limited RPM range and you don't have boost in the data.

Just do a 4th gear pull to redline at WOT if you want to know if you are lean and log boost! :)
The builders said not to go past 4500rpm during the break-in period. The motor currently has 250'ish miles. The tuner thinks it's running lean based on my "cruising speeds" as per instruction. I hit about ~8 or 9lbs of boost? AFR definitely not looking lower than 12 atm... I will do a new log otw and back from work tomorrow.

I agree but I don't think there's any evidence he is lean. And actually re-reading the original post he's only concerned with closed loop operations and STFT and LTFT. Anyway your approach is certainly safer if the driver has no feedback on A/F during the pull.
Update: The mounting points for MAF sensor on stock intake box was over-torqued and broken... Whomever installed it back into the car must have used an electric drill? Got a new piece and installed today. Will make new logs tomorrow, as of now AFR's don't seem to be any lower than ~12 for low boost from 8~10lbs. The motor seems to hesitate when shifting through gears under low boost and throttle input, almost felt like timing getting pulled but didn't see any fb knock or fine knock learn

thanks everyone for your input! check back for a new datalog soon
 

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Update: The mounting points for MAF sensor on stock intake box was over-torqued and broken... Whomever installed it back into the car must have used an electric drill? Got a new piece and installed today. Will make new logs tomorrow, as of now AFR's don't seem to be any lower than ~12 for low boost from 8~10lbs. The motor seems to hesitate when shifting through gears under low boost and throttle input, almost felt like timing getting pulled but didn't see any fb knock or fine knock learn
An incompetent shop, you don't say?
 

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Wow, I was so careful with the MAF as it has JIS screws and was scared as shit of stripping them when cleaning the MAF. I cant believe they didn't strip if it was able to crack the mounting.
 

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Discussion Starter #11 (Edited)
Hello everyone, new updates...

Got a replacement stock intake and also replaced the MAF sensor o-ring. Re-did a few vacuum lines that feed into the cobb EBCS, they didn't seem to be on tight enough with the tiny zip-ties.

Reset the ECU and went for a cruise and took a 5 min datalog. I tried boosting the car up to ~10 lbs and kept it under 4500rpm. I still saw no changes in the data... lots of AF correction and the AFR's are never below ~12.5. I see some feedback knock sometimes during these light cruising pulls and my fuel pump duty is at 100% at nearly 40% throttle position.

I'm starting to think either (A) My MAF sensor, front O2 sensor, or injectors could be on their way out....? or (B) There's seriously something wrong with the rebuild (OEM shortblock) or they totally missed something crucial during the reinstall....

The chassis has 96k miles as of now and 300miles on the new motor.

Checkout the most recent datalog here:datalog & basemap link
Can anyone review the .ptm file which is the actual basemap? I'd like to know if the map looks okay to some of you... THANK YOU

also considering taking the car back to the shop and just complain endlessly until it runs okay
 
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