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Tehnation's Ballin on a budget rebuild!


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I'm more leaning towards the injector/maf scaling because my maf sensor and wire harness were iffy, as well as the fpr. So the 1st tune settings might have been bad and trying to correct the issues but the motor didn't last long enough to get to that point. This soapy water test looks promising, I will try that out, but imo if its a vacuum leak its a device like the pcv or bpv, something u wouldn't see normally. I've replaced every vacuum line like 3 times over the past 5-7 or so years chasing bad fuel trims. Its hard to distinguish because of the cams, they will drop the vacuum naturally, but to what degree is the issue, a lot of factors go into that apparently so its hard to say what the vacuum should be. You can't base the leak on oem cam numbers! I have less vacuum but all my devices are running as they should, my fpr drops from 43-37 when the vacuum line is connected. The shop not the tuner said we should probably expect between 12-16 inhg for vacuum, which is where i'm at (6-8 psi), oem is more than that which is why people say its a leak! So vacuum leak is not likely the issue. 1 in hg equals like .5 psi!! Edited by Tehnation
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I'm not basing this on any vacuum numbers; it doesn't matter what cams you have. It's solely on a/f correction and a/f learning. The term vacuum leak just means one of the hoses in the intake track has a large enough leak to allow unmetered air to enter the engine. Due to this leak, there isn't enough fuel for proper ignition and the ecu tries to add as much fuel as necessary to get to the proper afr. Once the a/f learning is maxed out (+15) and your a/f correction stays high (above +15), the ecu will throw the p0171 code. Anytime the leak is major causes misfires immediately.

 

If it ran properly at all after the rebuild and then started the issues points to hardware rather than software though.

 

You might think of trailering it to your tuner on the dyno and let them figure it out, especially if you boost leak test without finding any leaks.

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I will say the build I had in mind is working the way I want it on a smaller scale. I wanted to spend more on cams than the turbo. A baller ass turbo is like 2k plus, versus 600-800 for some cams. I wanted the bigger cams to shift the power to the right as to make a more linear power curve. Normally people get massive turbos etc and max out power around 5-6k and then it plateaus. With the bigger cams it seems like I utilize more motor at first and then the turbo kicks in at the end. So I can cruise around under 4k rpm with plenty of power and like zero boost, but when I stay in a gear I get a bunch of power and by the time the turbo kicks in I don't really need it. I am speculating that when the car is dyno tuned I will see the power curve I have been looking for, hopefully it has enough fueling. I built it for 10k, hoping I can get what I want by 8k.

 

I'm just wondering why everyone opts to upgrade the turbo, block etc. and not the cams? Give the block more hp without boost and then the turbo is like a cherry on top.

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I'm not basing this on any vacuum numbers; it doesn't matter what cams you have. It's solely on a/f correction and a/f learning. The term vacuum leak just means one of the hoses in the intake track has a large enough leak to allow unmetered air to enter the engine. Due to this leak, there isn't enough fuel for proper ignition and the ecu tries to add as much fuel as necessary to get to the proper afr. Once the a/f learning is maxed out (+15) and your a/f correction stays high (above +15), the ecu will throw the p0171 code. Anytime the leak is major causes misfires immediately.

 

If it ran properly at all after the rebuild and then started the issues points to hardware rather than software though.

 

You might think of trailering it to your tuner on the dyno and let them figure it out, especially if you boost leak test without finding any leaks.

 

 

i am quite confident its not leaking, which is why i'm leading towards the tune being the issue.

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The car is still running lean at idle as the A/F learning 1 settled at 10.94. It shouldn't be misfiring anymore at idle though based on that log.

 

The tuner changed either the MAF Scaling or Injector scalar to add fuel.

 

At this point I would just keep sending logs to the tuner and let the tuner get you ready for the dyno. They'll let you know if there are issues.

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Your fueling is still quite off and the misfires returned from lean conditions.

 

Keep communicating and sending to your tuner. If the tuner makes changes but the fueling is still way off, then that points to hardware/leak (I'm not saying this is your issue, let the tuner do their thing).

Edited by rhino6303
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So, I swapped cylinder 2 and 4 injectors, and same thing . So its not the injectors. Got a set of coils coming tomorrow.

 

Got a set of 4 for 60 bucks

https://www.amazon.com/gp/product/B09GNBGCDR/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1

 

Coils and plugs tomorrow. Going to change an easy one first to see if it changes anything before changing the rest.

Edited by Tehnation
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305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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They were cheap enough where I figured I would try them out to see what happens, rather than swapping cylinder 4 coil with one of the misfire coils, which is a huge pita. I'm more hoping its the plugs. 20 year old technology, surely China's figured out a way to make it cheaper by now lol, 1 oem is more than all 4. So if it isn't the coil then whatever I didn't spend 300 dollars on new coils. If it is the coils then hopefully they can get me to inspection at the least, cause yea, this party needs to start at some point! I'm going to change cylinder 1 plug first then coil to see what happens, which is super easy, then take it from there but this slut needs to start putting out before I buy her more drinks! lol Edited by Tehnation
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I have like 20 used OM coils if you want 4 to try out, depending on your results with the Amazon coils. None are close to new, but none were removed for misfires either. Just coils that people elected to replace with brand new ones during their builds to be thorough.
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hmm. I changed #1 spark plug, but then I noticed that the plug has like zero gap... wtf ? So, new plug has like .32-.34, I gapped em all a while ago, but that was the range. If I get only 2 misfires then I found the problem, I'm praying to the subaru gods atm.

 

Not sure what happened to the spark plugs during storage but lets see.

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Only 2 came back this time, but I think I am calling the cylinder numbers wrong. I changed the front passenger, then P0302 went away.... or maybe I am celebrating to soon. Lemme change another and see what happens.
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Nope, same thing..... so its not the plugs, the coil packs look new as well, so I don't know whats going on. Any ideas why I am getting 3 misfire codes right away? Code timing cause this?

 

Before when I 1st got it started I wasn't getting these misfires so fast or at all I don't think. But as I started messing with the fueling its been getting worse. I'll change a coil pack tomorrow and see what happens, but I think its something else. Maybe I will swap back to the old ecu.

 

I don't even feel or notice the misfires. Maybe I should wait for it to learn the code 1st. The code is just in the pre code phase, is that normal to get codes and then they go away without bringing on the cel? Am I being to hasty?

 

I wonder if its going to eventually throw a code for all for or if its just 3, cause last time it was just 2. So maybe its happening at different times for each cylinder, and 4 just takes the longest?

Edited by Tehnation
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Is the CEL illuminated on the dash? Dobyou get codes when you pull using the accessport?

 

If so, clear them a d then check again. They don't go away on their own (I don't think).

 

Just to be sure, check that correct electrical connectors are in the correct location and maybe verify timing one more time.

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