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Previous Next Up Topic Engines / Subbug - Subaru Power / Fun trick with a flooded engine (6677 hits)
By Paul Moran (DBA Architect) Date 2007-08-28 00:26
My black Imp (EJ20) wouldn't start and after cranking, I could smell gas from the exhaust.  The LinkPlus was reading RPM, so I pulled the plugs and they looked fouled out (more on why this happened later when I have time).  I put some old plugs in that I had on hand and unplugged the injectors with the intent of turning the motor over a few times to clear out the cylinders.

Well, when I cranked it over, the darn motor started right up and purred.  It ran for maybe 5 seconds before it hit me that the injector's (all 4) electrical connections were unplugged and I turned it off.  Just for fun, I tried to start it again, but no luck. 

I put the injector connectors back on and it started right up.  I still can't believe there was enough gas in those cylinders (one I blew out with an air hose through the spark plug hole) to run for that long.

So hopefully its back to tuning now and it should be on the road soon I hope.
Chicago, IL
EMPI Imp 1002 ('69)/Subaru EJ20 Turbo/LinkPlus ECU
By Paul Moran (DBA Architect) Date 2007-08-29 03:32
Quick update on the Imp's EJ20 - I replaced the battery tonight and it starts up nicely. I'm hoping to take it for a ride tomorrow night.  Its a bit late to go tearing through the neighborhood.

So here's the run down on what happened - I don't think I posted this already.  I took the Imp to Fun Fest in Effingham, IL (about 4 hours from home - yes, a crazy idea but I went with the Buggistas).  I made it to Effingham ok, but I had to leave early Sunday to get to a Chicago Fire soccer game.  I kept missing the rain all the way home, but about 30 minutes from the garage, I got stuck in a good sized down pour.

My LinkPlus was riding on the passenger floor and had survived a few light rain falls in the past.  Its a dumb place to put it and I now have a nice sealed ammo box for it. Well, the buggy died on Rt 88 at about 55 MPH in the rain.  I towed it home and discovered the LinkPlus circuit board was fried.

Sent the LP in for service and an upgrade from V9 to V14 (the final version for a LinkPlus) for about $500.  They sent it back in a couple weeks with the burn circuits replaced by wires soldiered to the board.  I was knee deep in the new EJ25 conversion so I put it on the shelf and just before going to MI, plugged it in. 

It would barely start and ran terrible.  After racking my brain, futzing with the fuel map and other settings, nothing seemed to fix it.  We dragged it to the Silver Lake Sand Dunes for vacation and a couple days into vacation, I discovered that I had not hooked up the MAP line to the LP...  I reset it back to the original config from the V9 version and it at least ran, but the fan didn't come on and the fuel was still not right.  I did a bit of tuning (oh yeah - my LC-1 wide band O2 also seemed like it quit.  It kept saying "Heater circuit open", but after having it checked by Innovate Motorsports, it turned out to be a bad ground...) 

The Imp ran ok in the dunes with some more minor tuning. It had a flat spot or two, but by staying out of those map areas, it survived the week until it was time to go home. Then it refused to start.  I used an old Jeep trick of getting it onto the trailer and off via the high torque starter. 

Then it sat for almost 2 months.  This week I finally had a chance to look at it and found the plugs fouled.  I think the battery was also shot from the short circuit in the rain storm.

I still need to require it to put the relays into the ammo box.  I had it die earlier this year thanks to my main relay getting filled with water.  Note to self, put relays in a nice dry place.  I also am going to put fuses before each relay (actually before anything that draws power).  Thanks to Tom from for the words of wisdom on the ammo box, relay location and fuse ideas.

I also have to track down why the fan is not turning on when the water temp hits 190.  I double checked each ground as the LP sinks a relay ground to turn on the fan. I may have to send it back in but they assured me everything was tested before it was shipped back to me.

So that's my story for this summer.
Chicago, IL
EMPI Imp 1002 ('69)/Subaru EJ20 Turbo/LinkPlus ECU
By Southpaw Date 2007-08-29 11:13
Paul, Sounds like you have been having lots of Fun , HA HA . Till Next Time , Glen
Bremen Speed Equ. Citation #1077
By @Jeff GS Date 2007-08-29 11:19
Paul - that all souds like quite an ordeal - with some fun thrown in the mix!

I'm suprised you aren't ready yet to ditch that Link for something else - I think I would be!  But water and electronics don't mix - no matter what the ECU manufacture.

I'm thinking about putting my Megasquirt computer and relay board in smal polycarbonate enclosures, for just that reason.  They make these nice NEMA boxes that are water tight, but easy to drill for grommets and wiring pass-throughs.

By Terry F Date 2007-08-29 16:56
Paul - Just received my EMS Stinger from Outback yesterday (will post more about that later), looking though the instruction sheet I saw a note regarding the MAP hose. It states that if the hose is kinked the ECU will go to "full rich". That may explain why your plugs fouled when you fired up without it being plugged in...
By Paul Moran (DBA Architect) Date 2007-08-30 21:12
Yeah, I can appreciate "full rich".  Funny thing was the engine actually ran without the MAP hose hooked up. It didn't idle well, but you could rev it and I did make it around the block. I run TPS/MAP mode on the link so it may have been using the TPS signal to some extent.

Chicago, IL
EMPI Imp 1002 ('69)/Subaru EJ20 Turbo/LinkPlus ECU
Previous Next Up Topic Engines / Subbug - Subaru Power / Fun trick with a flooded engine (6677 hits)

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