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Discussion Starter · #1 ·
Posting for my boyfriend, NASIOC has not been any help, shops we have talked to have no idea, have tried changing every sensor, and checked wiring, re-grounded everything, checked for leaks, etc...I searched through alot of the threads on here and found nothing new to try, but hey maybe someone will have a really random idea that can fix things...

here is the issue copied from nasioc

Like the title says off throttle the car starts dumping fuel. Went to get it tuned saturday and we tried everything to to try and fix it. Swapped maf,ecu, checked all the wiring and nothing broken. ohmed out all the wires to the ecu from the maf and they check out fine. At an idle assuming you rev it will idle ok but as soon you rev it wont idle for crap. The tuner even tried tuning around it to see and nothing. Its def maf related because if I disconnect it itll run fine. Of course its a limp mode but you get the idea. Im stumped. Any input would be appreciated.

Tommy

04 wrx loading with fuel off throttle - NASIOC
 

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overdeveloped beater
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What ECU? TPS reading okay? The MAF is going to see air no matter what....but the TPS and MAP/MAF tells the ECU if the motor is in overrun, and if it should be cutting fuel or not.
 

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Discussion Starter · #6 ·
Its a RFL, been on the car forever and has never posed a problem, was on my old wrx before donating it to his 04.



318 was the wrx on that pass...ran at pinks all out with mods below

heres the mods before it had the issue..
2004 Subaru wrx 2.1L stroker
2.5 crankshaft
Mahle High boost pistons
Treadsone performance 50 trim rotated setup, 57mm turbo
TGV deletes
Port/Polish exhaust side of heads
1000cc DW inj
Opensource tuned by Motion Lab Tuning
3in intake
1 step colder plugs
Cx Racing FMIC
BPM catless exhaust
Custom header
TXS mbc

issue started being noticable after changing header back to stock for spool reasons, and getting new uppipe without any leaks, granted the car was still driveable, only acted up every now and again.
Now it has nitrous, and ran fine but was never ran with it, plan was to put new turbo on and get it retuned. Then when the new turbo 6069 was put on it stopped being driveable, and no one has figured it out since. This was back in November.
 

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Discussion Starter · #7 ·
Sorry for 2 posts in a row, but copying and pasting so everyone sees the same info. Here is what we have been through, both at the shop he works at, and at a subaru specific performance shop, and are now talking to another shop that deals with subaru and evo performance, and yet again, the answer is no idea. Grasping at straws at this point, but asking everyone possible... email convo with yet another shop..
Me:
So it is Tommys 2004 subaru wrx, was at your dyno day back in september or whenever. Changed the turbo on it to a percision 6069 and it began having even worse problems...

http://forums.nasioc.com/forums/showthread.php?t=2258599

Basically the MAF trips out, and loads it up with fuel and it wont run. Have had it on the dyno at 42 Autosports for 5 hours, trying everything and nothing has fixed it yet, changed sensors, smoked for leaks, they looked at the tune, checked wiring, grounding, etc... and the car is only driveable in limp mode. So it has got to the point where it looks like a standalone is going to be the only way around the MAF, unless you have any ideas as to what it could be.

But bottom line with the bigger turbo and the nitrous, it needs to be retuned, whether we figure this out or end up going with the stand alone, and he was impressed with the dyno day, and wanted me to ask if you were able to tune with a standalone.

Thanks, Summer / Tommy

Them:
Hmm, haven't seen that before. We could definitely take a look at it and see if we could fix it to try to save you the money of buying AEM and if not we can do the AEM.

Me:
He works at a shop so can get the aem at cost and can autotune it to get it to Hickory, and was wondering more of if you had any ideas off hand that could be posing the issue, and if not whether you could tune it when he gets it. Probably ordering it monday, how much would the tune run?

Them:
yeah that works fine. Let's start with what all you've changed and haven't changed? Do yall have any dyno graphs or logs of what it's doing? A tune on AEM will be $500, then retunes at $150/hr

Me:
As far as changed I have changed the MAF ,IAC, MAP, TPS, Coolant Temp, Egt has a resistor mod and changed it again to be sure. Basically every sensor on the engine and still nothing. The car is in time and has good compression and plugs are gapped to .025. Ohmed out all the wires also, pinned ECM to MAF and followed it through to battery and grounds and everything checked out. It kinda acted a little funny when I took the aftermarket header off and put the factory manifold back on for spool reasons and a new uppipe because the other was leaking. Got even worse when I put the new precision turbo on it and thats how it is now. Idk what else to do to it but eliminate the maf and go standalone which was planning on eventually anyways, but if the standalone is not the problem, idk. Seems tune related to me even though I had a tuner look at it and he said he couldnt do anything with it to fix or get around it. Even swapped ecus and put my map on the new one and it still did not fix it, yet it was running the same tune. Only thing I can figure is that it is either inside the tune somewhere, or something wrong that makes no sense.
Tommy

Them:
Did it start doing it all of a sudden? Or was it doing it before you swapped the turbos out? We could take a look at the map and put it on the dyno and see if we can see anything wrong with the map thats in it. Kind of hard to diagnose without seeing it

Me:
Started barely messing up once the header and uppipe was changed, then when the turbos were swapped, started it and attemped to drive, and thats when the problem got to where you cant drive it at all.

Them:
Hmm, i would check and make sure everything was done correctly when you swapped the things

Me:
it was, double and triple checked

Them:
I don't know what else to tell you then without seeing it or putting it on the dyno

Me:
I will let him know, the biggest thing is he has already had to pay once and been told "we cant figure it out," and doesnt wanna go through that again.

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So yeah, just a pain to limp mode the car 2 hours away, and pay for a shop to look at it with the only result being, ......dunno?! When he works at a shop and can keep trying things without having to worry about getting home. I feel like its something to do with the tune, but with that tuner looking at it and not seeing anything, idk.......UGH /RANT

Trying to brainstorm weird things than can cause issues, hell even checked the DRL resistor just cause you never know.

and if the ecu was withholding fuel wouldn't that be tune related?
 
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