Jump to content
Ultimate Subaru Message Board

EA81T ECS light on but then off at ransoms times


Recommended Posts

Hey guys. Yes I have researched this but everything I've read has had different symptoms or scenarios than mine. And I'm hoping what I've seen can eliminate the long list of troubleshooting parts. But if not I'll just keep trucking.

 

So I have a 1983 GL turbo wagon with the ECS light constantly on no matter how I drive it (when I do). I checked the codes and came up with ignition pulse system. My symptoms are while idling the RPMs drop and I hear popping in the airbox when I touch the throttle except half throttle or more it powers through it. There's been a couple occasions where I let the car idle for 15 to 30 minutes and the light went off and the problem went away. I don't drive the car so I go out every now and again and started it up just to run it. I've only had it out a couple times and actually one time last winter the light went off and the problem went away while I was driving it. Yesterday I started the car up and after about two minutes of warming it up the light went off and the RPMs blipped down at the same time and the problem was gone. I turned the car off and back on and the light was still off with no problem.

 

Are these specific enough sounding symptoms that can lead me to only a couple possibilities?

 

At first I thought it was maybe a running temperature thing since it's only gone off after fully warmed up but then yesterday on a cooler day and only running for 2 minutes did it go off.

 

Ideas?

Edited by PleiadesUnited
  • Like 1
Link to comment
Share on other sites

Maybe 15 years ago these symptoms would point to a specific problem, but these cars are over 30-years-old now.  Anything could be failing at this point and there aren't enough of these cars on the road these days to call much of anything a common failure.  Do you have a FSM, or perhaps the EA81T FSM supplement?

 

First things first, check ALL your electrical grounds in the engine bay and under the dashboard.  Make sure there is no corrosion, broken or frayed wires, missing wire insulation or broken connectors.

 

After that I would inspect the ignition system.  Take off the distributor cap and check for play at the rotor, there should be none.  How does the coil look?  Cracked or leaking oil?  How does the harness between the distributor and coil look?  Spark plugs and wires look ok?

 

If all that checks out, let's move on to the fuel system.  How is the fuel filter?  How is the fuel pump and wiring?  Put a long screw driver on each fuel injector while the engine is running and confirm that you can hear it firing in a consistent manner.  Does your TPS have a smooth, clean sweep from idle to WOT when hooked up to a multimeter?

 

I have seen the ECUs on these fail, so its possible that is your problem, but those are hard to find, so check everything else first.

  • Like 2
Link to comment
Share on other sites

  • 5 months later...

It's actually the connection at one of the two connectors that plug into it.  A guy i met had a spare one that I tried which made it run great.  Then that night the ECU died so I plugged my old one back in and my car started up but the ECS light was off but came on while I was screwing it back up.  So i jiggled the wires again and it went off.  So maybe it still is some connection within the unit or maybe a wire or maybe a connector, not sure.  But I do know that the light is now off and when it comes on I jiggle the wires and it goes off.  BIG weight off my shoulders as I was going crazy trying to figure it out.  The guy I met lives about 30 minutes from me and has turbo wagon shells all over and like 5+ brats laying around, a lifted EJ'd hatch, an all stock hatch and he said 5 more shells down his driveway that I never even saw.  Two greenhouses full of engines, transmissions, cars, parts and everything plus the kitchen sink.  I'm thinking of buying this '86 Brat off of him.  

  • Like 1
Link to comment
Share on other sites

It's actually the connection at one of the two connectors that plug into it.  A guy i met had a spare one that I tried which made it run great.  Then that night the ECU died so I plugged my old one back in and my car started up but the ECS light was off but came on while I was screwing it back up.  So i jiggled the wires again and it went off.  So maybe it still is some connection within the unit or maybe a wire or maybe a connector, not sure.  But I do know that the light is now off and when it comes on I jiggle the wires and it goes off.  BIG weight off my shoulders as I was going crazy trying to figure it out.  The guy I met lives about 30 minutes from me and has turbo wagon shells all over and like 5+ brats laying around, a lifted EJ'd hatch, an all stock hatch and he said 5 more shells down his driveway that I never even saw.  Two greenhouses full of engines, transmissions, cars, parts and everything plus the kitchen sink.  I'm thinking of buying this '86 Brat off of him.  

I'm in need of an ECU if you have a spare one. 7210

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...