Jump to content
Ultimate Subaru Message Board

EJ22T after swap problems. Fuel cut at 3 to 5 lbs of boost.


Steve W.
 Share

Recommended Posts

  Hi. folks, I,m back.  Well, I've had the car runnin' for a week or so, been working the bugs out.  Here are my issues now, the engine runs and sounds great, as long as you don't offer it any boost.  At first, about 5lbs., and total fuel cut, I aquired a spare ecu and swapped that in, it seems to run a little smoother, but dropped the fuel cut point to 3lbs. boost. I've run fuel pres. up and down the scale, but only managed to make it run richer.  I hooked up a speed sens. feed from the old ecu plugs, but not sure if that's working, because I did the same with the tach. feed,and that's not working. (It's a digi-dash)  Haven't been able to get a ck. eng. lite to work either. ( I mite' mention, so you don't have to look back, it's a 88 GL10T car, w/ a 93 EJ 22.t motor, loom & ecu.)  So far I haven't been able to push it hard enough to tell more than it has a bunch more torque, so hope to resolve this thing soon.  As always, I'm in debt for your guidance.   Steve.

Link to comment
Share on other sites

You need to try and get the check engine light setup so you can pull the codes from the ECU.  There's no point in trying to guess.  You can make your own check engine light by just running 12v to one end of a test light and then run the other end to connector F47, pin 19 (check engine light).  These pin outs may help if you don't already have them.

 

http://www.surrealmirage.com/vrg3/ecupins/

 

I will say that if you do not have a speed input going to the ECU it will most likely cause you some sort of weirdness and issues.  I don't know if it will limit your boost, but if there's any way you can get a speed input to the ECU, I would recommend doing that.

Link to comment
Share on other sites

Thanks guys.  I don't think I have any of the cruise stuff left.  How does it show on the pin out? Thanks Josh, I hard copied your pin out before i started this project. As i mentioned, I've attempted to hook up the spd. sens., not sure if i was successful or not. Not sure how to tell. I figured from the start that it could easily affect fuel cut, etc., maybe the tach. could as well.  I followed the EA wiring diagram, and felt the same color code from the ecu should feed back to the instruments, but not certain. I did notice that I don't have a ck. eng. lite fire up when the Ign. sw. is turned on, maybe just a bad bulb, I'll ck. it with a test lite in the morn., I am hooked to F47-19.  It seems I remember someone having problems with tach. feed and the digi-dash some years ago on a similar swap, I'll try to get some time to search it out. I got my wide band hooked up today, and was able to dial in the fuel pres, but no affect on the fuel cut.  It's got me scratchin' my head. I'm soooo close.  Thanks again fellas'.  S.

Link to comment
Share on other sites

It wasn't me with the cruise and VSS problem, I am using the original cruise computer and it all works fine.

 

Your digidash needs modifying to work with the EJ tach signal.

http://www.ultimatesubaru.org/forum/topic/101240-were-is-the-tach-wire-digi-dash-ej-swap/?p=1074396

 

Fix your CEL, do not pass go, do not collect $200.  It will tell you if your VSS is working or not.  If it has a VSS code use a multimeter with a frequency input to test, they are pretty common nowadays.

 

I wouldn't be surprised if the ECU will force no boost (fuel cut) if there are any codes that it deems might damage the engine under boost.

Link to comment
Share on other sites

Thanks Presslab.  I'm on it,  headin' out now to try Josh's test lite set up.  Hopefully that will set me in the rite' direction. Appreciate your tach. info, it's on the edge of my electronics abilities,  but I'll give it a try after I get these other bugs worked out. Thanks again,  S.

Link to comment
Share on other sites

   Well, now i'm really confused.  Set up as per Josh's instructions, but no help.  Powered thru my test lite to the CEL lead,  With Ign.sw. on, not running, constant lite.  Ign. on and running, no lite at all.  Now what? I ran thru my power and grounds again, with the pin out chart, it all looks good. It runs good. I feel like I'm back at point A, again.  I'll try switchin' out the ecu's again in the morning, but don't expect any thing to change.  Can't help but think it's something that I'm lookin' rite at, but not seein'.  Frustrated.  S.

Link to comment
Share on other sites

Hmmm.....

 

I remember I had to supply a ground to the pins at the original engine connector, to the pins that were originally grounded to the intake. 

 

Can't remember exactly why.....?  that was on an SPFI car. Analog dash.  Oh....I think it was to provide a ground to the dash for a VSS pulse to be generated? IDK, there was something that needed to stay grounded that originally grounded thorugh the ECU harness to the engine.

Link to comment
Share on other sites

   Well, now i'm really confused.  Set up as per Josh's instructions, but no help.  Powered thru my test lite to the CEL lead,  With Ign.sw. on, not running, constant lite.  Ign. on and running, no lite at all.  Now what? I ran thru my power and grounds again, with the pin out chart, it all looks good. It runs good. I feel like I'm back at point A, again.  I'll try switchin' out the ecu's again in the morning, but don't expect any thing to change.  Can't help but think it's something that I'm lookin' rite at, but not seein'.  Frustrated.  S.

 

Steve,

 

As I mentioned in the BBS thread.  Did you connect the diagnostic connectors when you had the test light hooked up?  What you described sounds like normal operation of the CEL with the diagnostic connectors not hooked up.

 

I agree with presslab, you need to get a functional CEL working on your dash as well as make sure the diagnostic connectors (black & green) are able to be connected properly to aid in troubleshooting.  Doing anything else before you can do those things is a futile effort and not worth your time or effort.

 

Link to comment
Share on other sites

  Hey,  Gloyal.  Do you think there mite be an old thread out there somewhere, that could cover grounding the old harness?  Doesn't sound out of line to me.  And Ivan, I like your thinkin', 

I'm sure I have an old needle valve around somewhere.  Worth a try.  CEL first.  Thanks ya'll.  S.

Link to comment
Share on other sites

  Hi. Folks.    Well, I dug out the test connectors, mine are both green, and I had cut one of them out in the strip down. So all hooked up, B56-13 and F47-14, set up the test lite, and (this just keeps gettin ' better,)  I get 5 fairly rapid flashes, a decent rest and 5 more at the same speed.  I kept thinking, no it's 5-4 or 4-5, but no, it's 5-5-5---.  The only thing in the 5 series are trany related, but still 2 digits. I'm cursed.  S.

Link to comment
Share on other sites

Steve,

 

You've got one of the pins incorrect.

 

The read memory connectors (black connectors) should be pin B56-pin12

The test memory connectors (green connectors) should be pin B56-pin13

 

Redo your wiring and then ground the read memory connector pin to see what codes come up.  Then groundthe test memory connector pin afterwards.  The proper procedure for the test memory check is on my site, www.surrealmirage.com/subaru/engine.html

Link to comment
Share on other sites

OK.  I'm all hooked up.  With the black leads connected, Ign. sw. on I get three codes.  24- air control valve, (is that the IAC?)  says it uses fuel cut to control eng. spd.  35- purge control sol., shouldn't affect how it runs rite?  44- waste gate, not in use.  Shouldn't affect performance either, no?  So it seems, air control valve the most likely? If that's the IAC, I do have a back up one. Didn't throw a veh. spd. sens. code, so hopefully that's working. Feels like I'm gettin' closer.  Whew,  S.

Link to comment
Share on other sites

#44 could be an issue.

 

I experienced fuel cut when the wastegate hose came disconnected on a test drive once.

 

Try hooking it up with stock boost control and see if it runs right.

 

IAC fuel cut is really only an idle control issue to prevent runaway idle ECU will cut fuel to #1 cylinder.

Edited by Gloyale
Link to comment
Share on other sites

You will need to plug in the wastegate solenoid or you can use an AT dropping resistor in place of it.

 

http://bbs.legacycentral.org/viewtopic.php?f=19&t=48079

 

The ECU can be cranky sometimes with the canister purge solenoid code.  If you have a spare you can plug in just to keep the ECU happy, I'd recommend it.

 

What are you doing now to control idle speed, and are you using the ej22t manifold so you could use the IAC valve?

 

Did you perform the active code check with the green diagnostic connectors?

 

I have a hunch that you may get a speed sensor code after the car has driven for a little bit.  That's what happened with me.  I would clear the code, and it eventually came back, but not right away.

Link to comment
Share on other sites

  Hi. Josh.  Well, I do have a spare purge solenoid and I'll try hookin' it up to see what happens.  Do you know what the resistance should be for the waste gate? I've got some layin' around, not sure what from.   One reads 6+, the other 13+, hoping one of these mite work.  I am running the EJ22t manifold and the IAC valve.   So, I ran the active code test this morning, here's the results.  Cold start, 50 deg. F.   Starts quickly,  idles hi, +or- 2000, (guessing, no tach.) for a min. or two, then goes lean, 22.4 and will die if not feathering the throt. for another min. or two.  Get past that and it idles at 800 or so, at an AFR around 17+,  that's at 30 psi. fuel pres.  I can adjust idle spd. and AFR by changing fuel pres.,  if you run the rpms up to 2000 or so, and hold it there for a bit,  AFR settles in at hi 14s - to low 15s,  snap the throt. shut, and it moves into the hi 12s - low 13s, before settling back to the low 17s where it will continue to idle.  Ok, with the Grn. connecters together,  Ign. sw. on, have a constant lite.  Now, do the full throt., 1/2 throt. etc., start eng., it blinks 5-5-5,  so on to the road test.   (note, while driving with Grns connected, AFR is in the hi. 15s - low 16s, but under deceleration it goes to the hi 11s - low 12s till the throt. opens, then back to 15-16s.  Again, I'd have expected it to hit 22.4)   Hope I'm not confusing you.  Anyway, I did get a whole new set of codes, ( 33- veh. spd. sens.  42 idle sw.   44- waste gate.  51- neut. sw.)  Now I ask, can I pick up the spd. sens. signal directly from the tranny sender wire?  It appears my tap at the old ecu connectors didn't work.  I have a spare throt. sw.,  wondering if that could be the cause of rich after throt. close problem. Had a similar issue w/ my EA motor.   Hoping resister takes care of the waste gate.  The neut. sw. code, maybe cause I don't have one, how can I fool it?   Clear as mud?   Again, I'd be in deep do-do if not for yous guys.  Thanks, S.

Link to comment
Share on other sites

Speed sensor signal comes out of the dash.

 

I woudl try grounding the black/red, black/yellow...etc. wires at the OE engine connector. Whichever ones were the original grounds I think 3 or 4 of them. The VSS needs the ground to pulse.

 

You can also get the Nuetral switch wire at the OE computer connector, as well as tapping in your EJ Tach wire.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...