Jump to content
Ultimate Subaru Message Board

EJ swap stalls...ideas?


jrettenmayer
 Share

Recommended Posts

Hey everyone,

 

I have a 90 EJ22 swapped into my 86 GL - engine runs great! Having never owned a subaru before this, it's been interesting figuring out all the little bugs that have come up since the swap. My most recent bug: When decelerating (i.e. coming up to a stop light and depressing the clutch, or slowing down to make a turn), the engine RPM will drop very low and then die. Does not happen all the time, or if I tap the throttle a little bit and sort of "control" the RPM drop down to idle then it's fine. And, it idles fine. The engine, wiring, ecu came from an automatic, though as I understand, it doesn't matter. I checked Pin 20 on B48 (found in another post - supposed to tell the car whether it's a manual or auto) and it is grounded - to the engine. Not sure where to go from here. Ideas?

 

I thought perhaps it was in need of a surge tank, but I am also under the impression that it's the E81 cars that need those. I filled the tank but the stalling still occurs. Car will fire right back up after the stall. Anyone else have a problem like this? The search function turned up some info, but couldn't find this specific problem.

Link to comment
Share on other sites

The ECU uses fuel cut during decelleration to give better engine braking and save gas. If you're going down a long hill with your foot off the accelerator, it's not injecting any fuel.

 

If you push the clutch in while it's doing fuel cut, the rpms drop way off and sometimes the ECU catches it and starts injecting fuel in time, sometimes it doesn't and it stalls before the ECU can start putting fuel in.

 

This is the reason that the ECU is set up to have a neutral postition switch, and a clutch switch. The clutch switch gives the ECU a heads up that you're about to uncouple the engine from the drivetrain, so it can start injecting again before you even have the clutch pedal to the floor. The neutral switch lets it use a different idle map when you're sitting at a light.

 

Missing these switches won't turn on the check engine light, however, if you plug the read code connectors together, it will give you clutch switch and a neutral switch codes. That's if you still have the diagnostic connectors and a check engine light wired in your swap.

Link to comment
Share on other sites

I have the diagnostic plugs (well, one of them, the other is MIA), but no CEL wired up. How do you suggest I fix the problem? wire in a clutch switch?

 

I'd say that would probably help you a lot. It's not a big job, and not like you've wasted a day if it doesn't work.

 

I'd say thats your problem though.

Link to comment
Share on other sites

After reviewing some wiring diagrams, it appears that the clutch switch activates the neutral switch? My wiring came from a legacy with an automatic transmission, so I don't have either switch. Where is the neutral switch located on the Legacy? Does anyone know if the EA has something similar that i can use? How have others gotten around this problem?

Link to comment
Share on other sites

After reviewing some wiring diagrams, it appears that the clutch switch activates the neutral switch? My wiring came from a legacy with an automatic transmission, so I don't have either switch. Where is the neutral switch located on the Legacy? Does anyone know if the EA has something similar that i can use? How have others gotten around this problem?

 

To be honest dude, I'm not really sure. I think the SPFI and MPFI EA82s had some sort of neutral switch, but don't quote me on that. I think they're located on the shifter linkage under the gearboot.

Link to comment
Share on other sites

There is a bolt on the clutch petal itself to adjust swing, or a switch, its your choice!:eek: IIRC its been a while on ea82s for me. But it should be the difference between non feedback and feedback and fi, shouldn't it?

Link to comment
Share on other sites

I saw the bolt - looks like there is maybe a spot to put some sort of switch also at the bottom of the clutch movement. As for the switch, do I need both the neutral switch AND the clutch switch, or will just putting in a clutch switch and bypassing the neutral switch do the trick? I'm hoping i can just connect pin 10 on B58 through the switch and to ground that will do the trick...

Link to comment
Share on other sites

Clutch switch will get rid of the drivability complaint. The stop bolt at the top of the clutch travel is what you want to put the switch in place of. The one on the bottom of the travel is for clutch-start interlock. It's to make sure the pedal is all the way down before the starter can work.

Link to comment
Share on other sites

This switch has 4 terminals - I used an ohmmeter to figure out that it can is always open on two terminals and always closed on 2 terminals, depending on what position the switch is in. So, if the plunger on the switch is all the way out, one set of terminals is open and the other closed. When you depress the plunger, the first set is closed and the second is open. Does that sound like it will work? I haven't tried it yet, but it seem is I should be able to just wire it up so that when the clutch pedal is at the top of its travel (plunger in), I can use the terminals that are open at that point, and when I depress the clutch, the switch will close and ground Pin 10 on B58. Sound reasonable, and feasible?

Link to comment
Share on other sites

  • 2 months later...

I have a similar problem with my ej swap. Except that mine doesnt die. I have a ej18 with a ej22 auto harness. So in that area we have the same stuff. But i have found that when my idle drops to +/-400 rpm's it always catches itsef. BUT, when drive (stop and go traffic) and I floor it, at about 7/8 throttle I have a huge bobble/surge, let off the throttle a little bit and its fine. Then it does away. I think I have narrowed mine down to an intake/vaccum leak. Just my .02, hope that might help.

Link to comment
Share on other sites

I have a similar problem with my ej swap. Except that mine doesnt die. I have a ej18 with a ej22 auto harness. So in that area we have the same stuff. But i have found that when my idle drops to +/-400 rpm's it always catches itsef. BUT, when drive (stop and go traffic) and I floor it, at about 7/8 throttle I have a huge bobble/surge, let off the throttle a little bit and its fine. Then it does away. I think I have narrowed mine down to an intake/vaccum leak. Just my .02, hope that might help.

 

Do you have your CEL hooked up? Mine does the full throttle bobble too, but only when the CEL is on. When it's off, I can floor it and smile:) As far as I can tell, the CEL gets tripped when I'm coasting. I'm assuming it's either the VSS or neutral switch not being hooked up that causes this. What else would the computer care about when coasting?

 

I haven't gotten around to diagnosing what code is doing it, though. The light seems to turn off by itself after a few minutes anyway.

 

Jacob

Link to comment
Share on other sites

Do you have your CEL hooked up? Mine does the full throttle bobble too, but only when the CEL is on. When it's off, I can floor it and smile:) As far as I can tell, the CEL gets tripped when I'm coasting. I'm assuming it's either the VSS or neutral switch not being hooked up that causes this. What else would the computer care about when coasting?

 

 

Do you have you're O2 Sensor hooked up?

 

I know with both my MPFI GL and my EJ'd wagon that without a O2 sensor, I would get a CEL every now and then at highway speeds, light or no throttle. When I stabbed the gas, it went away.

Link to comment
Share on other sites

Do you have you're O2 Sensor hooked up?

 

I know with both my MPFI GL and my EJ'd wagon that without a O2 sensor, I would get a CEL every now and then at highway speeds, light or no throttle. When I stabbed the gas, it went away.

 

Yeah, mine is hooked up. Those aren't quite the symptoms I'm having. I can't stab the gas and make it go away (but I wish that could be the solution to every problem:)). I need to hook up the VSS and neutral switch before exploring any other options.

 

Jacob

Link to comment
Share on other sites

No I havent hooked up the CEL, I am pretty sure mine is vaccum related. I have that huge intake and the fittings are not as tight as I would like. I also have the bigger vaccum line that is kinda kinked. Im pretty sure that the issue is vaccum. Mine does not happen everytime on coasting to a stop. It can happen just driving. I can feel it surge a bit and to the FLOOR test and its there. Drive a bit down the road and its gone. When I get around to fixing my vaccum line I will post how it works.

Link to comment
Share on other sites

No I havent hooked up the CEL, I am pretty sure mine is vaccum related. I have that huge intake and the fittings are not as tight as I would like. I also have the bigger vaccum line that is kinda kinked. Im pretty sure that the issue is vaccum. Mine does not happen everytime on coasting to a stop. It can happen just driving. I can feel it surge a bit and to the FLOOR test and its there. Drive a bit down the road and its gone. When I get around to fixing my vaccum line I will post how it works.

 

I didn't say it happened every time when coasting to a stop. All it takes is to do some engine braking at all to trip the CEL. About 1 to 30 minutes later, if I floor it, it bobbles. If the CEL goes away, I can floor it and everything's great.

 

I'm not arguing, I'm just being clear so that knowledge and information is shared.

 

Jacob

Link to comment
Share on other sites

No worries, I must have miss read that part. I will put my CEL light in and see what I get. If I floor mine, it most of the time wont go away. Its like it had a mind of its own. Drove it 50 miles today and didnt do it at all.

Link to comment
Share on other sites

No worries, I must have miss read that part. I will put my CEL light in and see what I get. If I floor mine, it most of the time wont go away. Its like it had a mind of its own. Drove it 50 miles today and didnt do it at all.

 

 

 

Pull the panel and the speaker from the drivers side of the dash.

 

Once you do that, you can reach in behind and find the SPeed sensor connector.

 

it's black, 2 pole, with a Yellow/red wire and a Black wire. It's one of those "T" shaped connecotors. Scavenge one from old harness (speaker connectors are the same, and many others)

 

Solder the wire that mates to the black one to ground and the other wire to the EJ VSS.

 

For the CEL....you need an extra pin from one of the round dash connectors. Pull one from an EA82 or another EA81 dash harness, and insert it into the #1(IIRC) spot on the white round connector. Hook the EJ CEL wire to that.

Link to comment
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
 Share

×
×
  • Create New...