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 Post subject: Why is my car falling flat on its face?
PostPosted: Mon Jan 30, 2017 6:02 am 
In Neutral
Joined: Mon Oct 17, 2011 1:37 am
Posts: 35
howdy,
I've got a 93 legacy turbo wagon manual swapped, which just got a td04 and tmic thrown on it.
At first it was sweet up to about 15psi (somewhere I read the ecu will account for 16psi???)
so after driving for a day I get a complete cutoff at random times....ie falling flat on its face.
I dropped boost to 10 psi with no change...
also checked and changed plugs, which did help a good bit due to being gapped .040, and now .032 or so.
But as the plugs helped a bit of hiccuping, it still will occasionally at wot, w/ only 10 psi, fall flat on it's face.


The codes that are being thrown are 12, (abnormal starter switch signal due to it being bypassed for now)
35, (canister purge solenoid valve) because I broke the darn solenoid so it's bypassed
and 51, (abnormal neutral/ inhibitor switch) because I haven't wired up my neutral switch
so all of those shouldn't cause any havoc to the tune based on what I read.

if the maf is being maxed out or bad 02 sensor or something causing spark/ or fuel to stop, wouldn't it throw a code?

possibly coils going bad?

um I dunno.....any suggestions?


Thanks,
Dustin





a little pic of the not so clenlinessness of my engine bay
Image


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 Post subject: Re: Why is my car falling flat on its face?
PostPosted: Mon Jan 30, 2017 6:54 am 
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Joined: Tue Aug 25, 2009 7:52 am
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Location: Des Moines, Wa
Are you running the stock ej22t ecu? It has fuel cut around 12-14 psi, depending on temp and altitude however. What is your vacuum at idle? Also, how about the vacuum hose that comes off the fuel pressure regulator (at the back of the passenger side fuel rail), I've seen the car do funny things if it's leaking air.

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 Post subject: Re: Why is my car falling flat on its face?
PostPosted: Mon Jan 30, 2017 6:42 pm 
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Joined: Tue Oct 15, 2002 11:37 am
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Location: Houston, Tx
You really need to make the ECU happy and deal with all the codes before you try troubleshooting anything further. Even if it's an unrelated code the ECU may do some funky stuff.

Did you pull out the TCU and do the MT/AT identifier pin wiring as mentioned in my swap write-up?

http://www.surrealmirage.com/subaru/swa ... rical.html

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surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

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


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 Post subject: Re: Why is my car falling flat on its face?
PostPosted: Mon Jan 30, 2017 8:05 pm 
In Neutral
Joined: Mon Oct 17, 2011 1:37 am
Posts: 35
yup, stock ej22t ecu.
the 12-14 psi fuel cut could surely be my culprit---shoot, I was under the impression it was all good up to 15psi or so..... I guess even thought I was around 10 it would spike up around that amount......

am I stuck keeping the boost below these levels?
it sure did feel great at 15psi when it decided to work :D

I did pull out the TCS and do the mt/at identifier pin.. btw thank you for the write up. it helped a lot. I did find however that I have quite a few wire colors varying from the diagrams, so I skipped a couple steps to get her driving.

the pressure line to the regulator does look solid... no pressure leaking.

Thanks for chiming in


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 Post subject: Re: Why is my car falling flat on its face?
PostPosted: Tue Jan 31, 2017 5:10 pm 
Fifth Gear
Joined: Fri Jun 20, 2008 8:17 am
Posts: 6202
Location: Lakewood, Wa 98439
I'm curious about your BPV routing. What else is that "T" attached to?

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91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT


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 Post subject: Re: Why is my car falling flat on its face?
PostPosted: Tue Jan 31, 2017 6:08 pm 
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imaiami wrote:
I did pull out the TCS and do the mt/at identifier pin.. btw thank you for the write up. it helped a lot. I did find however that I have quite a few wire colors varying from the diagrams, so I skipped a couple steps to get her driving.



Try the 92 FSM, the wiring diagrams will most likely better match than the 90 diagrams on my swap write-up.

http://www.main.experiencetherave.com/s ... and_Elect/

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Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

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


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 Post subject: Re: Why is my car falling flat on its face?
PostPosted: Tue Jan 31, 2017 7:48 pm 
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Joined: Mon Oct 17, 2011 1:37 am
Posts: 35
@mike-tracy vacuum at idle is about -20psi

@cj91legss that's just the valve cover breather t'd into that. All the intake hoses were brittle and breaking nonstop, so I just routed it all to the plastic box n made a makeshift S intake connection to use the remainder of the stock intake.

@Legacy777 will do, thx.


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 Post subject: Re: Why is my car falling flat on its face?
PostPosted: Tue Jan 31, 2017 8:14 pm 
Fifth Gear
Joined: Fri Jun 20, 2008 8:17 am
Posts: 6202
Location: Lakewood, Wa 98439
I would recommend routing the vc breather line. When your bpv releases air, it can go straight to the valve cover.

Sent from my SM-N920T using Tapatalk

_________________
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT


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 Post subject: Re: Why is my car falling flat on its face?
PostPosted: Tue Jan 31, 2017 10:39 pm 
First Gear
Joined: Thu Mar 26, 2015 5:11 am
Posts: 84
Location: illinois
imaiami wrote:
yup, stock ej22t ecu.
the 12-14 psi fuel cut could surely be my culprit---shoot, I was under the impression it was all good up to 15psi or so..... I guess even thought I was around 10 it would spike up around that amount......

am I stuck keeping the boost below these levels?
it sure did feel great at 15psi when it decided to work :D

I did pull out the TCS and do the mt/at identifier pin.. btw thank you for the write up. it helped a lot. I did find however that I have quite a few wire colors varying from the diagrams, so I skipped a couple steps to get her driving.

the pressure line to the regulator does look solid... no pressure leaking.

Thanks for chiming in


I was running about 16psi stock ecu with a fcd. I had the hks fcd and it worked great for me. I think I picked mine up new for like 110 but you can probably get a used one for 50 or so. I just sold it otherwise I would have helped you out lol go figure

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 Post subject: Re: Why is my car falling flat on its face?
PostPosted: Thu Feb 02, 2017 3:00 am 
In Neutral
Joined: Mon Oct 17, 2011 1:37 am
Posts: 35
@cj91legss for sure, it's probably not the ideal plumbing of the breather along with the bov, but I figured plumbed into the intake there's always going to be vacuum there, thus most of the air would go that way.

@marsh27 I very well may give that a shot.

Butt I'm also getting what seems to be clutch slippage when full boost hits, the whole 12psi, while in 4th or 5th gear at low rpm. It's quite odd cuz the clutch is nearly new, and it doesn't give me any slipping issues banging through the gears, or even launching. Nor do I smell any clutch. But when the boost hits the rpm starts running up really fast and then car isn't going much faster. I've played nearly 2k rpm of slippage, but then the car catches up to it gradually (this is of course while just trying to figure if the clutch is roasted) however no clutch smell and then no lack of grabbing anywhere else.

A buddy of mine seems to think it could be center diff, but I really couldn't see how it could slip fully free of the motor entirely.


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 Post subject: Re: Why is my car falling flat on its face?
PostPosted: Thu Feb 02, 2017 4:49 am 
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Location: Des Moines, Wa
When the center diff goes, it works fine when cold then has a banging/scraping noise once it's warmed up. I'm not sure why the clutch slips, but if the trans is NA and/or the clutch kit is a cheapo, anything's possible.

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1992 Legacy SS 5mt, reasonably modified ;)


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 Post subject: Re: Why is my car falling flat on its face?
PostPosted: Sat Feb 04, 2017 2:48 am 
Fourth Gear
Joined: Mon Aug 31, 2009 9:09 pm
Posts: 1204
Location: Rochester, WA
There's no way that the center diff could fail and cause that symptom. I'm going all in on slipping clutch as well, especially if it isn't a turbo clutch. If you have a hydraulic clutch setup, there's a simple way to run an 06+ WRX clutch on an N/A trans however.

Mike, I had a wagon once where the VLSD didn't fail in that way. It failed completely open, so it would roast one front tire from a launch all day long. Lol.

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2005 Legacy GT Limited Wagon 5-Speed. Stock-ish ;)


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