Boost Cut Issues on Robtune Code 44

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just-rust
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Boost Cut Issues on Robtune Code 44

Post by just-rust »

Been a long time since I have posted in here! Not sure how much traffic there is anymore but here goes:

1992 Subaru Legacy with 550 robtune, VF23, TMIC, Grimmspeed mbc, Grimmspeed uppipe, 3" bellmouth DP with AFR gauge

Had issues with boost and idle. Figured out the uppipe had a hole in it and was causing a rich condition and problems with boosting. Just swapped that out with a new Grimmspeed uppipe and idle and everything in vacuum cleared up. In boost it would cut instantly in hard throttle but you could creep the boost up to about 12 psi under a lighter pedal. Around 12 psi it would start bucking or cut out completely.

Changed plugs, wires, O2 sensor and checked all vacuum lines and intake fittings. Gauge reads -19 vacuum at idle. Disconnected the MBC and ran wastegate pressure. I can ease in and then run hard after it spools and it boosts but sputters up around the 10 psi mark using just the wastegate. Ran D-check and came up with Code 44 for the "Duty Solenoid Valve (DSV) Inoperative". I had thought this Solenoid wasn't used with the robtune. In D-check I turned the ignition to on and listened for clicking in this sensor and there was none. Pulled the bracket and the long rectangular sensor (Jecs A15-000 R40) at the rear of the sensor bracket was plugged in. I unplugged it and plugged in the DSV, heard clicking with ignition on and light went away at start up and it fully boosted with no issue on the first pull. After the first pull the light came back on and all symptoms came back. However now it is throwing non-existent Code 43 at me.

I feel like I am just in my head and missing something obvious here. Is the DSV supposed to be plugged in? I had pulled these sensors to look over during this debacle and did not pay attention to which sensor was plugged in. There is only one plug available so it is one or the other.
Rusty 1991 EJ22T - VF28 - '07 wrx TMIC - MBC - Invidia DP - Walbro 255 SOLD
1992 Legacy SS 5mt, with some neat stuff on it
Legacy777
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Re: Boost Cut Issues on Robtune Code 44

Post by Legacy777 »

Hi there,

I can't really speak too much about the Robtune setup as it's been too long since reading up on it. Have you tried emailing/contacting Rob with this question?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
just-rust
First Gear
Posts: 233
Joined: Thu Dec 26, 2013 4:22 pm
Location: Minnesnowda

Re: Boost Cut Issues on Robtune Code 44

Post by just-rust »

Thanks for the reply Josh! I am a bit lost as set-up was all done by Mike T. Like you, I haven't read up on it in a long time and my search skills are a bit rusty here. I have not reached out to Rob as of yet. Wasn't sure if he was still doing these tunes. I will post up on Facebook as well since it seems a lot of traffic has moved that way.
Rusty 1991 EJ22T - VF28 - '07 wrx TMIC - MBC - Invidia DP - Walbro 255 SOLD
1992 Legacy SS 5mt, with some neat stuff on it
Legacy777
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Re: Boost Cut Issues on Robtune Code 44

Post by Legacy777 »

Yeah, see what info you may be able to get on Facebook. I would still recommend trying to contact Rob. I was emailing with someone that was still talking with Rob.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
just-rust
First Gear
Posts: 233
Joined: Thu Dec 26, 2013 4:22 pm
Location: Minnesnowda

Re: Boost Cut Issues on Robtune Code 44

Post by just-rust »

Ended up pulling the intake side and re-tightening everything and replaced a couple of hoses. Boost is back and I suspect it was in the TMIC piping. Such a weird code but luckily it turned out to be an easy fix once I got to the issue. It is crazy how hard these cars pull. Especially after lots of crap runs. Thanks for the replies Josh!
Rusty 1991 EJ22T - VF28 - '07 wrx TMIC - MBC - Invidia DP - Walbro 255 SOLD
1992 Legacy SS 5mt, with some neat stuff on it
Legacy777
Site Admin
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Posts: 27891
Joined: Tue Oct 15, 2002 11:37 am
Location: Houston, Tx
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Re: Boost Cut Issues on Robtune Code 44

Post by Legacy777 »

Welcome!

Glad it was an easy fix.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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