mm88swrt Posted November 18, 2012 Share Posted November 18, 2012 decided to make my own thread to pertain to my vehicle model! as stated it's an 87 ea82t. i do not have spark from the coil. just put a rebuilt motor in! fired up with no problems and about an hour into it the tach freaked out and the motor fell on it's face.all mechanical aspects of the motor are working properly. have 12v on both sides of my new coil. got a new to me ditsy out of a running vehicle. as stated in another post the green and white wire are different on the 87s. i switched the wires with no results. do not have any codes from the ecu. fuel pump does not turn on when key is on due to the ignition system not working correct? i'm beating my head on a wall with this one, can't seem to figure it out. in my head something had to of fried electrically just from the nature of how it ran great then ate s**t. maybe the ecu? Quote Link to comment Share on other sites More sharing options...
Cougar Posted November 18, 2012 Share Posted November 18, 2012 Even though the ignition isn't working you should be able to hear the fuel pump turn on for a couple of seconds when you first turn the key to the RUN position. First verify that fuses 5 and 12 in the dash have power getting to them. If the horn works fuse 5 is good. Also verify that the fusible links are good and are located in the plastic box mounted on the coolant reservoir. Quote Link to comment Share on other sites More sharing options...
mm88swrt Posted November 18, 2012 Author Share Posted November 18, 2012 All fuses are good under dash and so are the fusible links. I checked for voltage on the plug the ditsy plus into and only one wire had 12v going to it. Not sure what the readings should be at that plug. Quote Link to comment Share on other sites More sharing options...
Cougar Posted November 18, 2012 Share Posted November 18, 2012 The fuses may be ok but have you verified power is getting to them? If that checks out then you need to see if the fuel pump relay is getting power. Quote Link to comment Share on other sites More sharing options...
Gloyale Posted November 18, 2012 Share Posted November 18, 2012 Do the Check engine light, and LED on ECU come on? Disty is turning correctly? just to clarify. I have ECU's if you need them. Quote Link to comment Share on other sites More sharing options...
Gloyale Posted November 18, 2012 Share Posted November 18, 2012 Key On/Engine Off Body side of harness voltages: Red wire from pin 7@ECU - 10v or more (power supply) White wire from pin 17@ECU - 4v or more (Reference volt) Green wire from Pin 8@ECU- 4v or more (position signal) Black/Red wire from pin 20@ECU- Ground to intake. Now looking really close at the Diagrahm....it seems there are 2 completely seperate ground paths for the ECU, from 2 Eyelets bolted to the ECU at different points. One of them, is the ground path for the disty, throttle sensor, and a few others. To be clear about the the wire swap...it's the White and Green wires, of the Body harness of the car that get swapped.....leave the disty pigtail itself intact the way it came off the car. And only swap those wires if you are using a disty from an 88+ in an your 87. Quote Link to comment Share on other sites More sharing options...
mm88swrt Posted November 19, 2012 Author Share Posted November 19, 2012 Do the Check engine light, and LED on ECU come on? Disty is turning correctly? just to clarify. I have ECU's if you need them. All idiot lights come on when key is on, but no led from the ecu. I'm searching for an ignition amplifier to replace the one I have to see if it fixes my problem. Also running tests on the other things. Quote Link to comment Share on other sites More sharing options...
Cougar Posted November 19, 2012 Share Posted November 19, 2012 (edited) Since there is no sign of power getting to the ECU and the fusible links are good you need to check the ignition relay since it switches and supplies power to the ECU. You don't need to be concerned with the ignition area at least until the ECU has power to it. The ECU must have power getting to it first. The info I have for an '88 model (hopefully it matches yours) shows power should be on the following pins: Pin 27- power from fuse 5- blk/wht Pin 29 an 41- power from ignition relay- wht Pin 49- power from ignition relay- red/blu Edited November 19, 2012 by Cougar Quote Link to comment Share on other sites More sharing options...
mm88swrt Posted November 20, 2012 Author Share Posted November 20, 2012 So the ditsy volt readings came out in spec. I DO have power going to the ecu. And power where it needs to be on both the ignition and fuel relays, yet the fuel pump does not kick on when I turn the key on. Still no led on the ecu when I turn it on. I've found a ignition amplifier so I will hopefully have that tomorrow. I'm going to try and find two new relays just in case. Power on both sides of all fuses. Quote Link to comment Share on other sites More sharing options...
Gloyale Posted November 21, 2012 Share Posted November 21, 2012 No LED on the ECU means at least part of the circuit board isn't getting power. Or that the ECU isn't working.....Might try a different ECU. Quote Link to comment Share on other sites More sharing options...
Cougar Posted November 21, 2012 Share Posted November 21, 2012 I agree with Gloyale, if power is getting to the various power leads of the ECU then it appears it has a problem since the LED isn't working. Quote Link to comment Share on other sites More sharing options...
mm88swrt Posted November 21, 2012 Author Share Posted November 21, 2012 My car was originally an auto. So would I need an auto ecu? Or would the pins be the same from a manual vehicle? I have a manual one i can pick up today Quote Link to comment Share on other sites More sharing options...
Cougar Posted November 21, 2012 Share Posted November 21, 2012 I think the ECUs are the same for either transmission. Quote Link to comment Share on other sites More sharing options...
TomRhere Posted November 22, 2012 Share Posted November 22, 2012 I think the ECUs are the same for either transmission. Correct. In searching for why my CEL is always on, I found that the ECU's are the same. Difference is in the bodyside wiring/plugs for the ECU. Auto trans vehicles have a couple more wires than the manual trans ones. Quote Link to comment Share on other sites More sharing options...
mm88swrt Posted November 22, 2012 Author Share Posted November 22, 2012 Ok so here is an update. Got a used ecu out of an 88... Installed all my new parts (ignition ignitor and such). I HAVE SPARK!!!! BUT I AM NOT GETTING ANY FUEL!!! All the tests ive ran out of my manual say to replace the control unit. The ecu i pulled out of my car has the number 36 on it. The one I got in there now has a 20 on it. Are the pins different from those two ecu's? I am kind of thinking I need a "20" ecu. Seeming as i have spark now, I am holding the ecu accountable for this mess! Quote Link to comment Share on other sites More sharing options...
ivans imports Posted November 22, 2012 Share Posted November 22, 2012 nope disstributor pu whould be my gess is the crank and cam senser all in one if you lose the crank senser part no spark if you lose the cam senser part no feul check the wire harness on plug at bottom of diss or coil ground or diss ground. Ecu fails very rarly and will ushaly run with bad ecu just not properly. Or the ig fusabble link is bad or shorting Quote Link to comment Share on other sites More sharing options...
Gloyale Posted November 22, 2012 Share Posted November 22, 2012 (edited) You sure no fuel? No fuel pump operation? or No injector pulse. Can you jumper the Fuel Pump relay and get the pump to work? If not check pump ground. If you have spark, you should have injector pulse. Ivan, there is only one sensor in the disty of EA82. Edited November 22, 2012 by Gloyale Quote Link to comment Share on other sites More sharing options...
Gloyale Posted November 22, 2012 Share Posted November 22, 2012 Ecu fails very rarly and will ushaly run with bad ecu just not properly. I've got a stack of non-operational EA82, SPFI ECUs. Replaced 3 this year. The Fuel pump driver circuit actually fails commonly. There was a board member about 3 or 4 years ago who actually documented replacing the power transitor on the board to fix it. Quote Link to comment Share on other sites More sharing options...
Quidam Posted November 22, 2012 Share Posted November 22, 2012 Just some thoughts. I personally took out a 3AT Loyale ECU when I hooked up the battery charger backwards. It had no led after that. Back a ways there was talk of the coil wires hooked up backwards. Would that do it to? I installed an '88 5 speed ECU, known good and it wouldn't run the car. I swapped in an '88 AT ECU and the car has been running ever since. I used an ebay seller that listed the actual Hollander interchange information for my car, and the MT ECU's weren't compatable. If you had that Hollander info from somewhere, it would clear it up for you. Doug Quote Link to comment Share on other sites More sharing options...
mm88swrt Posted November 22, 2012 Author Share Posted November 22, 2012 (edited) Positive no fuel. I will check for injector pulse later today if I can move . There is power every 1.5seconds to the fuel pump pin at control unit(55) and power to the fuel relay. It seems to open and close just fine. I get the one click from it when I turn the key on, but still no pump noise. I'm also going to hardline my fuel pump to 12v to see if it works. Random note of the day my ecu is popping up with trouble code 44... Wtf is code 44 it doesn't exist. Also for me to get spark from this ecu I had to swap the white and green wires that go to the ditsy. If I hardline the open side of the fuel pump relay in turn that should kick the pump on correct? I'm just really thinking I need an ecu with the number 36 on it, not 20. I have a feeling there may be a slight difference!!! And my coil wires WERE backwards when I first installed the motor. The yellow wire from ditsy is just the tach wire correct? I want to delete the digi one in my dash. I've got an aftermarket one. Edited November 22, 2012 by mm88swrt Quote Link to comment Share on other sites More sharing options...
Cougar Posted November 22, 2012 Share Posted November 22, 2012 (edited) It sounds like you are now making good progress. My info shows that the return side for the fuel pump ties to ground so if you have voltage getting past the fuel pump relay to the pump then the pump should turn on unless there is an open wire connection on the blue wire to the pump or the pump itself is bad. To verify things are working otherwise, you should be able to spray a small amount of starter fluid into the intake and make the engine fire up. I think the yellow wire not only ties to the tach but it also is used to provide the pulses for the fuel safety circuit. Edited November 22, 2012 by Cougar Quote Link to comment Share on other sites More sharing options...
ivans imports Posted November 23, 2012 Share Posted November 23, 2012 weird never seen a bad ecu on ea82 t mabee just never came up before anyway have 4 of those ecus all good. I very rarly ever see a bad ecu mabee two out of 2500 cars both had shorted wire harness. One was loyale spi turbo other was a outback 3.0 six Quote Link to comment Share on other sites More sharing options...
mm88swrt Posted November 26, 2012 Author Share Posted November 26, 2012 Problem has been solved!!! Tracked it down to being the ecu. I have a feeling there are a few differences between auto and manual trans ecus. I got an auto ecu out of an 89 gl-10, and put it in my car (green white wires swapped) and the fuel pump started working again. Car runs great again and now I have an all new ignition system lol. Thanks everyone for all the help, it helped me out a ton. Hopefully this won't happen again!!! Quote Link to comment Share on other sites More sharing options...
Cougar Posted November 26, 2012 Share Posted November 26, 2012 There is a fairly common problem with some of the ECUs from that time. It sounds like your unit may have a controlled ground for the fuel pump through the ECU. There is a driver transistor that drives the output transistor inside the ECU that is a common failure item. I have repaired a couple of them in the past. The same transistor was at fault on both of them. You might have the same problem with yours. Thanks for the update and glad you got things running. Quote Link to comment Share on other sites More sharing options...
mm88swrt Posted November 26, 2012 Author Share Posted November 26, 2012 Yes that could very well be the problem. As far as my original ecu goes, that thing is toast lol. The other one may just be the problem you're speaking of. Thanks again for all of your help! Quote Link to comment Share on other sites More sharing options...
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