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Link G4X Problems on Subaru Wrx 2006


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Hi !

So i just bought a WRX with some problems it seems. I have issues  with the idling and overall performance of the car. Cant find out who tuned this car or how stuff is setup, some strange history... hoping that someone here can point me in any kind of direction regarding possible faults , broken sensors and so on... ive never done any kind of tuning to a car before but ive built alot of cars and i know what im doing mechanically, got this pretty cheap so i figure i can learn on this. Atleast its cheaper than to blow up my supercharged c6 with 1058hp xD


Sometimes it starts up with really poor idle, sometimes it just backfires after some cranking

Plz help a n00b out here 


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Ok, this looks like you have what we call a "V10" wrx, usually 2.5L DBW, but from the trigger scope it appears it has been fitted with an EJ205/207 engine.  

I see a few issues with the cam sensors in your scope and log.  There are 3 cam sensors on the EJ205/7, one at the front behind the top left cam sprocket that is used for "sync" and one at the back of each head on the intake cams used for the VVT position.  The original 2.5L engine only had the two cam sensors at the back and never had a seperate sync. 

  1. The cam sensor at the front has been wired incorrect polarity, you need to swap the +/- wires.  This will likely be the cause of the start up issues. 
  2. It appears neither of the AVCS cam sensors at the back are working, in fact I suspect one isnt even connected.  This would explain some of the lack of performance as VVT would not be working at all.  We are probably going to have to shuffle some wires around to free up the correct inputs since this ecu was originally only designed for 2 cam sensors and now needs 3. 

I suggest you fix #1 first, this should at least allow it to start reliably.  While you are there take a look at the rear cam sensors and check if both at least have wires running to them.  Do us a new scope and log with it running, then I will try to give some better direction on how to fix or diagnose the rear cam sensors. 

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Thank you very much for your help! So i switched the polarity of the front sensor without any improvement. Also took a quick look at the wiring they have done, it seems they have connected the front and rear passenger side sensor together in a series. This whole car is a electric mess from what ive seen so far, also i talked to the last owner who said it drove well for a while with this map and after a while got worse and worse. The connectors for the sensors are plugged in on both sides in the back, tho the front and back left side are wired together.


I also see there is a fault in the FP Speed at idle, not really sure how its all wired at the back but ill take a look. Also attach the log of standing on idle switched polarity



So its a "Forged" 205 in it

TD05 Turbo

Intake TGV Delete

STI Injectors

Walbro 255L Fuelpump (not sure it can run off pwm ?)

Grimspeed 3 Port boost control solenoid

Bigger Rad 


I think thats all, and ofc upgraded clutch and so on... 


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Ok, polarity of front cam sensor looks correct now, but voltage is very low, this is probably due to it being wired in series with the other one.  We are going to need to fix that.  Can you pull the ecu out of the case and confirm if it is a 04-06 or 07 ecu, it will be printed on the board near the expansion connector, similar to my pic below.  Once I know what ecu it is I can then give you the correct instructions for how to wire the cam sensors.

The fault reported on the fuel pump aux is normal in these and you can ignore it.   



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Also from my understanding connector to the left is a. And a14 should be trig1 ground, for me its unconnected?

I better get a multimeter and start to ring all cables into the ecu. From the looks of it it seems that one of the wires from pass side cam trigger goes into b35 just looking at color. If so its a miracle this car even ran at all… 

Extra picture to show you what kind of elctric installations im working with here…




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Yep, A14 is the green in your A plug.  



2 hours ago, Ripzek said:

also took a picture of the jumpers. For me it seems like they are installed uncorrect?

Jumpers are likely correct, the ecu wouldnt power up and the fuel pump wouldnt work with them in the wrong position.


Now for the cam sensor wiring:

Trigger 2 (pin A21) was originally connected to the Left rear cam sensor, we want this to go straight to the front cam sensor now.  The front cam sensor should have only 2 pins - one is sensor ground and the other is signal.  The ground may come from the rear cam sensor or can go back to the ecu.  These two wires should really be in shielded cable. 

The right rear cam sensor should have just worked with the factory wiring so shouldnt have needed any changes but it doesnt appear to be working in your triggerscopes so you may need to investigate what is going on there.  It should have +12V, Ground and the signal pin should have continuity back to ECU pin A11 (DI2).  Pic of pinout below is looking into the sensor housing.

The left rear cam sensor pinout is the same as below, so again you need 12V and ground to the sensor.  The signal I would connect to pin C25 (DI4), this was originally used as the clutch switch.  



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OK, As the JDM stuff is a bit weird compared to AUD and US stuff  ( It catches a lot of people out..) Are the Triggers in the back of the Head 2 or 3 Pin ( As Adam mentioned..) but ALSO check The Cam itself ... If the triggers are slots cut into the cam, then you need to use the 3 Pin type, If it looks like the end of a Mace.. its the 2 pin type.


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Alright, ill go down to the garage after lunch and have a look. Both rear sensors are 3pin, crank and front cam sensors are 2 pin. 

Ill check the triggers in the back also. 

The car is sold new in Sweden tho, and i think the engine came off a Swedish car also. 

Stupid question im sure of it but when you talk about left and right side is that from inside the car or front of the engine xD. ?


So to clearify, i have 2 magnetic sensors (2pin) one at the crank and one on top of the right cam (facing engine) and 2 hall effect sensors (3pin) on both sides back of the engine. 

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Alrighty, spent the night in the garage rewired the things you told me. Now it starts better but idle is still crap, rumbling and so on. Ill post everything so you professionals can have a look if it seems ok.


Ecu Settings.pclx

Triggerscope Swapped Cables.llgx Triggerscope 2 Swapped cables.llgx

HereIdle Log switched wiring.llgx is also the log 

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Lots of stuff I dont like in that tune.  I have made some changes and attached it below.  Load this in and do us a new log, hopefully is will idle more stable but dont be alarmed if it does not, the idle base positions are just guesses so may need to make some tweaks before it is happy.  Its also running very rich but I havent done anything with that, lets get it idling and all cam sensors working first.

If it idles with this tune do us a new trigger scope too.  

You can use the >file>compare function is you want to see what I changed, if you open my map first the open your original map using compare, all differences will be highlighted red.  


Idle changes.pclx

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Superb, you are a rock Adam! This tune and ecu install was made by a self proclaimed Subaru ”Guru” in Sweden…

Yeah ive seen that function, compared a little with Link basemap vs the one i had in it. 
Ill load it in as soon as i can sneak away a little from work and into the garage

Didnt find my old strobegun from the megasquirt days so ill get one today and check timing also. 

But everything seems to be ok with the triggers now? Just made a quick jumperharness to try, if its all good il do it properly.

Once again, thank you for all your assistance. You make me feel excited about learning to tune/setup ecu’s. Have always been a headache before


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The front cam sensor now looks good.  The left rear one that you have just connected to DI4 wasnt set up in the software so I didnt expect that to work yet, but I have set it up in that tune above.  The right rear cam sensor is still not working in that last scope and should have been. Did you confirm it had 12V/gnd and the signal pin had continuity back to the ecu A11?  It could be that it does have mismatched cams in it for the sensors as kaptainballistik suggested above, but there are a couple of further tests we can do to confirm wiring is good.  

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Hmm, that was odd. Well i have 2 new sensors to pick up at the post office right now so i guess i will connect them and see. Was it dead in both scopes? Had the +12v wired to a switch if something would shortcircuit, dont trust this wiring at all and havent had the time to sort it all out yet. Mabye i was braindead and turned it off on one scope. Ill remove the camcovers and have a look also. 

4 minutes ago, Rozsko said:

Unfortunately there are lot's of them around the world.

Haha yeah thats true, i dont understand ppl like that. Just be humble and honest about what you know and the skillset, otherwise its impossible to learn. Atleast now its no harm done so far. Had another guy who blew up my fuelinject modded SB2.2 engine a couple of years ago because he was a ”expert” in autoverdis drysumps and chevy engines… Heard it run 2 min atleast xD

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1 hour ago, Ripzek said:

Was it dead in both scopes?


One test you can do, if you are using one of our default layouts, on the main configuration page you can see the DI statuses.  If you pull the rear sensors out (but leave them plugged in) and place an iron object in front of them, if the sensor and wiring is ok these statuses should turn green and say "Active".


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Hi again! Im back xD

So here is the trigger and logs from after changing to your config/tune. It idles so well now! Its like night and day. 

Feels good that i could  see some light in the tunnel, for a while. Until i heard a really strange sound on the right bank, was like a low muffled clunking sound. But it was inconsistant and did not follow rpm or throttle. This is my first ever boxer engine, any clue ? Guessing something properly bad XD

Rear sensors is still dead from what i saw. I will pickup the 2 new ones later tonight and give it a go, i also have 2 bosch sensors here from another build i can test with.


Link do Idle log, this max file size is killing me... : https://stegia.sharepoint.com/:u:/s/SubaruWrx2006EJ205-LinkEcu/ER9uc0WTiqNCgbBFd1bMOtgBPNMB4pe5C_LReqIizCSFFw?e=Y6FZro

Trigger Adamw file.llgx

Idle log adamw file.llgx


Oh , now the brain turned on here on the forums. It is a max size set for the threads so i have to delete old files. Got it

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The share point link doesnt work, you might have to check the sharing permissions.  The forum host only gives each user a small upload allowance, and it is quite expensive for us to increase that allowance, it is best to share files using onedrive or google drive etc once you have reached that limit.  

Yes, rear cam sensors are still not showing any signal.

From the log I can see the idle base position is a little low, you will need to tune it better later, but for now if you highlight that whole base position table and type "+0.5" it will add 0.5 to all values and it will be closer to the ballpark.  

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Intake cam fun... Now what AdamW said is right 99.9% of the time. But if you ever wander into the black hole of JDM motors you find some odd stuff. Hence my question on if its an import motor. Its caught a few people out. There was a trigger change on the 2.0 that started around 2004 model year. Its normally an issue when you use a motor originally from a liberty. 

Its easy to check from the 2-4 Bank, just undo the rear sensor, Its pretty obvious when you look in there.

Its Highly likely that What AdamW said is correct and your cams are the Hall effect type, and if not.. its also likely they can "work" with a Hall effect trigger if they are not. ( i think the sensor height is similar.) NASOC indicates it can be done, But i don't trust NASOC.

JDM 2.0L pre 2008 (Single AVCS) Has 4 trigger lobes for avcs and thus must use the trigger on Cam 2 ( Cylinder 2-4 bank). In JDM cars these use a Reluctor trigger (2 wire)


Post 2008/ 2005 Liberty 2.0L DAVCS (Commonly referred to as a the Ej20x) Now for extra fun this is whats apparently in a 2005 USDM 2.0 These DEFINETELY use a Hall effect (3 Wire) 2.5 WRX/STI cam is the same as this. Due to having a "missing" tooth, It doesn't need the front cam trigger.

Yes, I have a lot of spare Cams. :D


V9 AVCS trigger 


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Hi again


Due to halloween and alot of booze i didnt manage to work on the Subaru. Now ive removed both rear sensors, they both look like the first picture you posted kaptainballistik. Ive got 4 lobes on lh cam and rh cam, does that mean i need to change the sensors ? Not quite sure how you mean

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You will need to check your AVCS trigger config matches a 2002-2004 STI. The correct cam sensor is a "Drop in" fit and is the same as the crank sensor.

( I mentioned earlier that the 3 wire units apparently can SOMETIMES work.. with some serious stuffing around with config, but personally I would fit the correct ones...)

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