wagondragon Posted June 28, 2014 Share Posted June 28, 2014 So i recently bought an 87 subi wagon, it had intermittent spaz sessions where it would lurch from low rpm to high. it happened under load most. I think tracked it down to the FI system, most likely electrical... i thought i fixed it with a new rotor and cap as it ran well for about a mile... when it completely stopped getting fuel. My fuel pump is fine. but I tested the FI itself and it its impedance is out of spec. I'm not sure if that can cause it to fail to inject fuel or not, but currently my next move is to get a pick and pull fuel injector that passes the ohms spec from the book. ive got all the pieces of the puzzle except fuel to get her started again. Any of you guys think that the spaz sessions, and the not starting is the same issue? Is there anything i haven't thought of that could be causing this issue? If so which systems would be good to check? Thanks in advance. Link to comment Share on other sites More sharing options...
jono Posted June 28, 2014 Share Posted June 28, 2014 have you looked for any codes on ECU. I know some say no codes will show unlss ecu light is on, not suree if that is Sube specific as my S1 EA82T mpfi had an error in it without ecs light on, fixed error problem, on my way. I think these S2 EA82 mpfi - it is mpfi ?? not spfi ?? had a doo dad near coil, but not part of coil bracket, that has a ceramic outer and provides some sort of electrical need for the injectors on turbo side strut tower on RHD Link to comment Share on other sites More sharing options...
john in KY Posted June 28, 2014 Share Posted June 28, 2014 Fuel filter is known good, right? Link to comment Share on other sites More sharing options...
wagondragon Posted June 28, 2014 Author Share Posted June 28, 2014 Yes, fuel filter is good. tested the psi on either end of the filter 20 psi all the way. The fuel stops at the injector, for some reason it is not firing or it is plugged up. And yes i checked the codes, it says the fuel injector is not firing. ( its exact words are a little different... but thats the jist of it. ) Its SPFI, non turbo. There is a kind of fuse box over there, but i cant think of anything else, maybe thats what your talking about jono? Does that provide electrical to the FI system? Link to comment Share on other sites More sharing options...
wagondragon Posted June 29, 2014 Author Share Posted June 29, 2014 Swapped the FI with a pick and pull, also the Throttle Position Sensor, started when i first installed, but after about 5 seconds it shut off. Now its not spraying fuel anymore. ECU is still sending the code that says the FI is bad. Or atleast that its not injecting fuel, for whatever reason. So i think im down to bad ECU, or bad electrical someplace in the system... Link to comment Share on other sites More sharing options...
jono Posted June 30, 2014 Share Posted June 30, 2014 oh STOP it, you will be giving Tweety the horrors ! He had a rather nasty experience with spfi conversion, now it is hello Weber ! OK, disclaimer is I know nuttink about spfi, just got the inlet manifold and its throttle body ,, the electrical resistance thingy about the mpfi of 87 onwards, do not think is for spfi at all. It looks to be inside a white ceramic just like resistor housing material on a points resistor Link to comment Share on other sites More sharing options...
wagondragon Posted June 30, 2014 Author Share Posted June 30, 2014 Yeah... i put a weber on my 85, runs great. But i bought the 87 for its 5 speed and some of its electrical parts for 350$ off craigslist... couldn't pass it up. Mainly trying to get everything running to make sure it all works before donating it to my 85. Link to comment Share on other sites More sharing options...
gdudik Posted June 30, 2014 Share Posted June 30, 2014 20 psi seems awful low to me. My Chilton's says 36-50psi with engine running. Link to comment Share on other sites More sharing options...
jono Posted June 30, 2014 Share Posted June 30, 2014 i have found that the desired pressure could not be checkd for unless the fuel gauge is T'ed into the fuel pressure line not just as an end of the wall measure. 35 psi seems to be about the normal mpfi running pressure T'ed in Link to comment Share on other sites More sharing options...
wagondragon Posted June 30, 2014 Author Share Posted June 30, 2014 I think the SPFI PSI is lower... I'll double check my manual. I seem to remember it being right on when i was checking it. Link to comment Share on other sites More sharing options...
wagondragon Posted June 30, 2014 Author Share Posted June 30, 2014 I was looking through the troubleshooting section and it mentioned a resistor that doesn't appear to be in mine... If i can track one down thats my next best guess. Link to comment Share on other sites More sharing options...
wagondragon Posted July 4, 2014 Author Share Posted July 4, 2014 Well, im pretty sure the resistor is for newer models. So thats out... I'm going to try the ECU next. I tested all the wires and sensors that i can think of that are connected with the FI system and they all seem fine. The only thing that was bad is that the FI was not getting volts from the ECU when i tried to turn it over. Unless there is some other system that can stop the ECU from sending to the Injector, like a fail safe. I'm assuming its the ECU. Link to comment Share on other sites More sharing options...
wagondragon Posted July 4, 2014 Author Share Posted July 4, 2014 So does anyone know what years they used the same ECU? i went to a wrecking yard and the model numbers were different than my 87... Help! Link to comment Share on other sites More sharing options...
jono Posted July 4, 2014 Share Posted July 4, 2014 it would help yourself and others if you volunteered what info you have on the ECU model number, and as it seems you found other model numbers - list them too . The info won't hurt sitting in the archives. Link to comment Share on other sites More sharing options...
wagondragon Posted July 4, 2014 Author Share Posted July 4, 2014 Ill have to get those when i go back next time. I guess i was mainly wondering how much difference they had between models. If that was knowledge someone had... Link to comment Share on other sites More sharing options...
naru Posted July 5, 2014 Share Posted July 5, 2014 (edited) So does anyone know what years they used the same ECU? i went to a wrecking yard and the model numbers were different than my 87... Help! Only 87 SPI ECUs are compatible according to the parts book. 22611 AA200 and 201 I`d pick a 201,if I had a choice,but,I would check the wiring between the injector and the ECU plug first. Edited July 5, 2014 by naru Link to comment Share on other sites More sharing options...
wagondragon Posted July 5, 2014 Author Share Posted July 5, 2014 Thanks for the feed back... now to just find an 87 near me... I also checked the wiring from the ECU to the FI and its going through just fine. Just not getting the message to fire when plugged in. Link to comment Share on other sites More sharing options...
wagondragon Posted July 6, 2014 Author Share Posted July 6, 2014 Fixed! It was the ECU all along... damn dirty thing... thankfully there was ONE 87 in my area that was FI. Started right up when i swapped it out. Next to check if all the components i want to swap over to my 85 are good. Thanks for the feedback fellas! Link to comment Share on other sites More sharing options...
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