Lean condition after Treadstone install. p0171
 

Hey guys,

I have been trying to narrow down a lean condition on my 14 BRZ.

Treadstone 6758 kit

omnilink 4 bar map sensor

deatschwerks 340lph fuel pump

turbosmart on turbo bov

vacuum line is currently tapped between the intake manifold and the booster check valve.

I currently have my post o2 sensor at the bottom of my downpipe, narrow band o2 in the middle and my wide band at the top (closest to the compressor housing)

So far I checked the mating point at the header, the v-band connection at the up pipe (which had a little bit of soot) and the vband connection at compressor housing to downpipe. Applied copper permatex to all v band connections but I'm still reading high values on my short term fuel trim which is causing my cel to kick on (now about 150 miles)

I'm currently running a base map from trust auto but the problem was consistent even with my original treadstone map.

Let me know if anyone needs any additional information, definitely open to hearing your opinions.

btw, I've already suspected the maf which iv cleaned and I have not looked further into the narrow band values yet.

Car has 20,xxx miles.

Innovate LC-2 in my case was recommended to be placed at least 18 inches away from the turbo's discharge. What specific WB are you using?

Do you have a datalog to share? If you have a display connected to your wideband are you seeing the lean condition reflected in the displayed values? Base maps are just a starting point. You should never drive normally (using full boost, heavy acceleration, etc...) until your tuner has had a chance to review the datalogs and made any fine adjustments.
-Matt

I'm using the downpipe provided by the full Treadstone kit so the bungs for the o2's are all stacked in a row.

I'm using an aem uego wideband.

I do have data log, I will upload it in a bit from my last drive. My wideband does and doesn't reflect my lean condition. The lean condition is constant but visually not present on my wideband because my car is constantly compensating the fuel trim to prevent a lean condition. So to be exact, I am not "currently" running lean due to the fuel compensation but I throw the code because the compensation stays consistently high.

I have been going back and forth with my tuner and I have been staying out of boost and emailing datalogs. My tuner has made some adjustments but due to the fact that my fuel trims are so high, he can only do so much on his side until I find the reason for the lean condition.

https://www.dropbox.com/s/lnjzzqy8qv...35-20.csv?dl=0

Here is the last data log I did of the car. This was taking a mild cruise around the city specifically data logging my short term fuel trim vs long term fuel trim.

https://www.dropbox.com/s/lnjzzqy8qv...35-20.csv?dl=0

Here is the last data log I did of the car. This was taking a mild cruise around the city specifically data logging my short term fuel trim vs long term fuel trim.

Still on the OEM injectors? I'll have a look in a bit....

Well it looks like the fuel trims are at their worst when running just DI, which is most of the time in that log. Did you disconnect the DI ECU on the LHS of the engine during the install? It's also clear that your A/F Learned for the PFI is much lower than the A/F learned for Dual injection.

You could just bump up the MAF and adjust the PI to suit or work out why the DI isn't delivering enough fuel. That's if there's no other hardware issues.

I had P0171's and after chasing down and fixing my exhaust leaks, it turned out to be a vacuum leak. Verify the integrity of those two systems first.

P0171 SUBARU - System Too Lean Bank 1 Possible causes:
Intake air leaks (Vacuum leak)
Faulty front heated oxygen sensor
Ignition misfiring
Faulty fuel injectors
Exhaust gas leaks (before or at O2 sensor)
Incorrect fuel pressure
Lack of fuel
Faulty Mass Air Flow (MAF) sensor
Incorrect Positive Crankcase Ventilation (PCV) hose connection

Start with the basics. Do a smoke test and see if you have leaks in the intake or IC piping

I have the pcv hose connected to the intake on the nipple next to the air filter. I suspected a dirty of faulty maf but Ive already cleaned it and I haven't had the chance to trade with another frs/brz on my lot. ive currently chased down and patched up all suspected exhaust leak areas. no current misfires. There is a possibility that the o2 is bad but everything was working 100% prior to the turbo kit install which is wahy I'm leaning away from faulty sensors.

A few months ago I was in contact with Treadstone (which btw has the worst knowledgebase and customer service) and they had to ask about 4 people in their shop before letting me know to d/c the green evap connector under the manifold to plug up the boost control wires. Can anyone confirm that this is correct.

Yeah, most tuners use the evap solenoid wiring for boost control. Did they include a properly terminated harness or did you have to splice the wiring yourself? Did you install hose clamps on all of the vacuum hoses under the manifold? They tend to come loose under boost. Also did they include a replacement PCV? The stock one doesn't like boost either.
-Matt

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