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persistent P0246 code - I'm at a loss...

4K views 8 replies 2 participants last post by  svswan 
#1 ·
This one is driving me crazy and I'm hoping someone can help.

Got my JDM EJ205 with Avic installed, got everything sorted and can't get the P0246 to go away. FBCS shows 30 ohms and will actuate, but I bought a GS BSC anyway 'casue I want to tune for faster spool up if I can.

I have 12v on the yellow wire, and continuity to ground from the BCS connector to pin 24 on the ECU B137 connector.

After following factory diagnosis instructions I have this -

#1 - 12v at pin 24
#3 - BCS disconnected - 12v between pin 24 and ground
#4 - 30 ohms stock - 32 ohms Grimmspeed
#5 - I'm pretty sure the connection is not bad, especialy since I get voltage from wire to ground with BCS unplugged.

I have a Tactrix cable and RomRaider. I tried resetting the ECU. I changed the ECU (have both USDM and JDM) and same thing, can't get over 9lb boost. I clear the code, check to see it's gone, then start the motor and it comes back before I even drive it.

I'm about to get some sage and eagle feathers and maybe a rattle to try chasing the Evil Code Demons away >:D>:D

Anyone have an idea? And Hello everyone - first post here ;-} I have a '91 Volkswagon Vanagon with the heart of a 2004 WRX. 3 months after buying the van I lost coolant and warped the motor. Ordered up the JDM EJ205 hoping to get a bit more power with the AVIC's but I can't at 9lbs !!! Thx
 
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#2 ·
does this mean that I managed to check everything and there is nothing left to check? I read somewhere about someone who had a similar problem and it turned out to be a leaky BOV on the intercooler. Trying to figure out how to test that...

No thoughts on this?
 
#3 ·
Hook up the stock BCS, reset the ECU, and go for a short ride. Try to build boost briefly and see if the P0246 comes on right away.

If so, your ECU's switching mechanism is toast.

you'll probably need a new ECU is that is the case. find one from a junkyard for cheap and copy your map over to the new ecu.
 
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#4 ·
Thanks Titter -

I will try swapping to the stock BCS and give it a go. If no luck I'll switch to my JDM ECU and try again. I would think both ECU's would not have the same issue, though I have tried both with the Grimm BCS. Fortunetly I'm just starting with tuning and would not loose any hard work if the ECU was messed up.

Love the look of your nose with the extra lights in the grill ;-}

swn
 
#5 ·
My wife reminded me that I have been letting the yard work slip as I incessantly focused on my vanagon. I have not had a chance to change out the BCS yet but hope to tomorrow night. Don't want you to think I don't appreciate your imput Titter...
 
#6 ·
lol its all good bud dont worry about that.

i should say that i dont mean you need a different ecu. if the problem is the switching mechanism, replacing it with the exact same ecu should work. but in that same sense, the JDM ecu might work too. you need the JDM ecu anyways if you want to run AVCS. so if it turns out the switching mechanism is toast in your JDM ecu, you will need a new JDM ecu. also make certain this is 100% the cause before you start buying ecu's lol.

ps: those are hella horns behind my grille. i just painted them to match the car.
 
#7 ·
Still haven't put the stock bcs back in. Partly because I had the code before I took it out and replaced it with the grimm bcs, and partly because I just got caught up on other things. Spent all weekend celebrating my 50th too ;-}. I got some time tonight to try something and instead of replacing the stock vacuum lines and bcs I swapped in the spare alternator off my warped ej205. I was hoping there was some weirdness with the voltage regulator causing the ecu to think the voltage on the bcs was 'high'. No luck. I'm going to try the fbcs tomorrow, and recheck continuity and grounds tomorrow afterwork. If that doesn't work i'll be tempted to just stretch a spring off the waste gate arm...

I like the horns then ;-} I've been looking at the Nautilus horn, are you happy with the hellas?
 
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