Dies hitting boost after harness swap(UPDATE) FIXED!!

[Doaomo]

Did you get the harness from cotruckin (Jarrid)??? Jarrid is still there in Denver with all of our parts, we should have a few more harnesses for you if this one does not work.

[cj91legss]

fmic

[alexandermf]

Yes on the fmic! That'll be my next mod IF my car ever gets fixed yes got it today Dave, Dan said he was gonna get on it tomorrow... I'm usually the hopeful one always seeing the glass half full, but after this mess, if the harness doesnt fix it idk what to do.... There's nothing else to look at

[Someperson]

Really weird issues... Have a full working harness out of a 94 im buying on sat if u need the cab harness

[Legacy777]

Thanks for the update.

Keep us posted if the new harness fixes things. Are you replacing just the engine harness or the entire front bulkhead harness related to the engine?

[alexandermf]

I personally haven't seen it. I paid for an "engine harness" but seller said it was complete from driver seat to fuse panel under hood? I dont know what consists in a bulkhead. They got a guy putting it in Dec. 12 so ill def keep ya updated!

[alexandermf]

While Its down ill def be looking to convert to fmic, been reading threads all day and it looks like the cx racing is the best to go with?

[cj91legss]

Probably, Make sure you read up on your spots you have to cut into the car or what not. Also keep in mind modifications you have to make to your bumper beam. and lastly DON'T OVER TIGHTEN THOSE T-BOLT CLAMPS. They will break easily.

In the past i've had issues with regular clamps not tightening good enough and couplers blowing off while under full boost (Not f*cking cool) so i bought some cx racing clamps, and being newb to them i'm just like f*ck it torque them bitches!!!!!

Also, since you're going cx, buy an 11mm ratchet wrench, it'll save your life

[alexandermf]

Well its been about 3 months and the car is still down.. seems like everytime a problem fixed a new one arrises so here we go:

We finally replaced the engine wiring harness which was diagnosed bad that was causing intermittent shorting to cause no spark.

New wiring harness is good and we got spark and then my brand new O'Reillys fuel pump was only creating 20lbs of pressure and it was dying with ANY load applied to engine.

Now we put a walboro in and its running smoother and holding fuel pressure but now its dying when it hits boost... We are stamped beyond belief and have replaced a variety of parts... I will copy and paste a list of what Brian(working on it) has done and I'm sure he will chime in later on to see if anyone has an idea of what to do

[alexandermf]

That's really all I can find, ran a spare ecu if mine an a tcu an narrowed the rpm rev to the idle air control valve. Can't get the code to clear at the moment, but I have replaced the knock, cam,crank, wastegate purge control solenoid, map sensor, pressure sensor, igniter, tcu, cleaned the mass air flow sensor, replaced vacuum lines, throttle position sensor

[alexandermf]

It's really when it hits boost that it wants to die not really a load but boost so I gotta figure out the boost... All my regular resources are stumped.

[alexandermf]

Codes are 24/35/44 idle air control valve / evap pressure/ wastegate control solenoid valve, going to swap the iacv(24) tonight

[alexandermf]

Fixed loose iacv, no change... Brian is brainstorming/rethinking what it could be, if anyone has anything to throw at us plz chime in!

[91legacyawdturbo]

On Alex's car before the bulkhead harness swap we had codes 11/13/22/24/31/35/44/45.
After the bulkhead harness swap the ecu has flagged the iacv, emissions purge valve, and the wastegate control solenoid, codes 24/35/44.. The parts I have replaced goes as
Fuel pump
Camshaft position sensor
Crankshaft position sensor
Knock
Oxygen sensor
Mass air flow
Iacv
Igniter
Coil
Plug wires
Vacuum lines on the fpr, purge valve.
Ecu
Tcu
wastegate control valve was capped off and a mbc was put into its place. Before the break down.
The original ecu cannot control the car, won't stay running to allow the car to idle or anything else starts and immediately dies.

The car will run if you don't let it boost. As soon as boost does come on it dies off looses power. Rpm drops to 1000 rpm.

Next step is to swap the intake manifold/ engine harness since swapping the iacv an purge control valve since booth are hard fault codes.

[Legacy777]

These ECU's can sometimes become cranky...including not clearing other erroneous codes when the canister purge solenoid is not working. Have you verified whether the solenoid is working and in the specified resistance range it should be? If not, I'd suggest doing that, and checking the wiring from the connector to the ECU.

When the car loses power when you build boost, does it completely fall on its face like fuel cut or does it just kind of sputter out?

Forgive me if you've mentioned this previously, but have you verifed every single wire and pin going to the ECU from its end point? I know this sounds like an extremely tedious process, but it is one of the few ways to completely rule out wiring issues. I did this when I put in my stand alone because I wanted to verify every single pin out and wire, so I wasn't chasing ghosts. I discovered the knock sensor wire was bad.

Take a look at the ECU I/O I put together when I did my stand alone. It's more complete then what's in the FSM.

http://main.experiencetherave.com/subar ... p_rev7.xls

The wastegate solenoid may also be causing your issues, again, I'd check the wiring and solenoid to make sure it's in spec.

[alexandermf]

hey everyone sorry for the delay on my responses, its been a hectic trip trying to drive the car from denver back to colo spgs and try to get another shop onto it for a second looksies and i have lots to update you on!!

but the problem still persists, its just easier for me to explain the codes and whats going on now that the car is back in my possession so plz feel free to chime in at all when you see the essay in my next post

[alexandermf]

Update #1

get the car back from denver feb. 17(sunday) and drive it down to colo spgs with my stock boost controller and no boost gauge(they had taken it all out when did the wiring harnesss swap job)

so as long as i stayed out of "boost" the car was fine. If i hit "boost" it fuel cuts ever so gently(like an angels sneeze) lol and gets back up to rpms. so it stumbles for like half-full second and gets back into it. pretty much i have to drive it like a grandma if i dont want it to fuel cut. anyways on the highway drive back home my top speed was 78 ish and my highest rpms were 3.5k without fuel cut. now.... fuel cut would range between 2-3.5k just depending on my throttle load/boost level

Update #2

get it back to the springs and take it to my buddys shop where he helps me look at it all day. we ended up reinstalling my prosport electrical halo series(great accurate gauge from what ive seen) and LITERALLY fuel cut happens at 0psi and im cruising cozy fine when the vac is at 1. I could push the needle to 2psi by cruising at 1vac and pushing the pedal to the floor. the car also can go into power mode but fuel cuts as soon as it hits 0 like all the other times.

so after this we found quite a few air leaks in my POS spectre coupler/brass fittings in my intake setup after my maf. so we thought my boost problem was from that with all the unmetered air entering after the maf we thought the ecu was maybe freaking out. well after a good ole trip to the local siliconehoseintakes warehouse down the street we de-jankified my setup with a 2.25-->3 in silicone 90 coming off the turbo to a 3in aluminum 90degree to a 3in silicone coupler and there are DEFINATELY no leaks anymore! so its actually running maybe a tenth better lol.

ALSO ever since i got the car with the hose setup(fpipes and connections rerouting back to intake) i could have my car running and unscrew my oil cap or take my dipstick out and the car would just stumble and die.... never ever caused a problem but we fixed it by rerouting the pcv hose and hoses coming from valve covers and now the engine doesnt die with oil cap being unscrewed!! such a weird thing and everyone was a confused until we brought a complete stock turbo first gen next to mine and traced like little kids the hoses and found out we could eliminate alot of the mess

Update #3

sooo finally after the car being at the shop all day and not fixing the main problem we were looking to fix i pulled 10 codes from the check engine light/black connectors under dash..... make sure you take in mind that half of these codes were from us at the shop pulling sensors/injectors/etc to try to solve my fuel cut problem.

Codes:
14, 15, 16, 17---> all injectors
24-Idle air control
33-vehical speed sensor(my speedo cable is making noise behind dash so it either needs lubed or replaced and my speedo cable is delayed/stays at one spot sometimes)
35-canister purge solenoid valve
44-duty solenoid valve(wastegate control)
45-pressure sensor+pressure exchange solenoid valve ******* this code seems to be culprit cuz on our code symptoms page this reads: Prevents abnormal supercharging pressure using "fuel cut" in relation to engine load... which is exactly whats happening to me
49-air flow sensor

[cj91legss]

Replace those boost sensors

Sent from my SGH-T989 using Tapatalk 2

[alexandermf]

Here's a pic of the extra hoses we removed which remedied the air pressure in oil system.


Pic of new hose setup, all the excess shit we removed used to be where that brass connector between the black hose is at.(the middle hose of the three pictured coming off intake setup)


Behind shot of the 2.25 to 3" silicone 90 off the turbo(absolute largest you can jam between the intake manifold for sure!... It used to be a 2.25 90 silicone to a shitty 2.5 plastic spectre elbow to a shitty plastic spectre coupler that was cracking bad....

[alexandermf]

So 34, 44, 45? If we have a running turbo lego can I swap one at a time to see which one is the fix or do I for sure just need to replace/buy them all in the long run? Also i tried leaving my power lead off my battery for 5-10 mins and it didn't clear the other codes... If I leave it off all night will they clear by morning?

[cj91legss]

should clear after all night. If you have a running turbo legacy then you should swap the map first, the the pressure exchange second (drive it in between) Brand new those parts are going to kill ya. The Map is 392 bucks from subaru and the pressure exchange is somethin like 98 bucks

[alexandermf]

holy shit! def not going to be buying new then from heuberger so change map then drive, then change press exch solenoid(which is located where exactly?) we disconnected my map while the car was running and it didnt stumble or die then we did it to my buddies which is running well(minus misfiring on cyl 1) and his did the same thing so i thought that may have ruled out the map?

[alexandermf]

are most of these solenoids/valves im getting codes for ALL located in intake mani?

[Legacy777]

Can you draw a diagram of how all the PCV hoses are hooked up?

Have you tried using the green & black connectors to clear the codes? Also, have you tried just the green connectors to see what code it may indicate? I would suggest these two options if you can't get the codes to clear.

DON'T just go replacing sensors. You need to do more diagnostic checks to rule out that list. With your fuel cut issue, I'm pretty confident that you have a MAP sensor or map sensor wiring or hose issue.

[alexandermf]

i will draw a diagram before work and put it up late tonight when im off! it was soooo fudged up before and we kinda made it better i wouldnt doubt it being some sort of problem...

well i did read about the black and green connectors to clear but from these instructions is slightly confusing...
http://www.legacycentral.org/library/li ... /codes.htm
i just dont get the 01, 02, 03 and so on blink(what its supposed to look like for each one and what they mean) and after im done when will the cel light blink to show me the active codes? after my 7mph drive or right when the engine starts up? maybe if theres a better instruction page i can look at i can get a better idea of what to do

thats what my other friend said, he thinks its a map sensor issue but if the sensor from another car doesnt work do i go right for the wiring or should i assume my map is good and its a hose issue.

also if i get the day offf(cuz its snowing and probably slow) ill go back to the shop and start doing all this today