s!lvias30 Posted December 4, 2009 Author Share Posted December 4, 2009 Yea you were correct I was able to identify the 1978 ecu , and yes I had a 1978 wiring harness and a ecu 100% sure , also I have been using a 1978 280z FSM PDF file from xenons30.com so I'm sure I'm doing I good . The efi I have is for a 1977 but I know the pins are not the same so I use my fsm one that is correct, ok a little help which pins on the ecu are suppose to be hot ? Thanks for the help , for real I have been carless for 3weeks about to be a month too ! Best help ever hope u can guide me to fix this Quote Link to comment Share on other sites More sharing options...
s!lvias30 Posted December 4, 2009 Author Share Posted December 4, 2009 Never mind I get it now . Ok I will do it right now , give me like 5 mins Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted December 4, 2009 Administrators Share Posted December 4, 2009 I think understood you to say that your wired the '78 harness exactly to the '78 FSM and are using a '78 ECU, ('77 ECU was a spare and now realize it wont work at all with a '78 harness.) If you rewired your '78 harness to a '77 diagram?.... If all is good, then using the FSM wire diagram you should be able to trace out which wires are supposed to be hot and when. Also double check that your EFI relay is indeed the correct one and operating correctly. They changed internally and I am pretty sure the '78 EFI relay is particular to itself, i.e. you can't use a different relay on the '78, (not 100% sure on this one though). Quote Link to comment Share on other sites More sharing options...
s!lvias30 Posted December 4, 2009 Author Share Posted December 4, 2009 Ok I just finished , the only pins that were at 12 volts were ; pin 15 = injector number One , pin 33= injector number two, pin 32= injector number three, pin 14 = injector number four , pin 30 = injector number five , pin 31= injector number six, pin 1= ignition coil, so yea what is next step Quote Link to comment Share on other sites More sharing options...
s!lvias30 Posted December 4, 2009 Author Share Posted December 4, 2009 Ok I had spare harnesses and ecu but they were 1977 ones , I'm using a 1978 and the efi relay I had bought it new and it clucks one and close when I turn the key , it's a 1978 also the 1977 are every different also are the harness . Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted December 4, 2009 Administrators Share Posted December 4, 2009 Ok I just finished , the only pins that were at 12 volts were ; pin 15 = injector number One , pin 33= injector number two, pin 32= injector number three, pin 14 = injector number four , pin 30 = injector number five , pin 31= injector number six, pin 1= ignition coil, so yea what is next step Based on the FSM, what pins are "supposed to be" HOT +12 volts when the key is turned on? There should be at least one other pin that is hot, i.e. power "for" the ECU, maybe more. If they are not hot when they are supposed to be, start tracing those wires back till you find out why they are not hot. ... I'm using a 1978 and the efi relay I had bought it new and it clucks one and close when I turn the key , it's a 1978 also the 1977 are every different also are the harness . I have no idea what you just said? English must not be your native language? Quote Link to comment Share on other sites More sharing options...
s!lvias30 Posted December 4, 2009 Author Share Posted December 4, 2009 Honestly I can't find it in the fsm which one are supposed to be hot so I don't know Quote Link to comment Share on other sites More sharing options...
s!lvias30 Posted December 4, 2009 Author Share Posted December 4, 2009 And yes I'm Spanish lol Quote Link to comment Share on other sites More sharing options...
JSM Posted December 4, 2009 Share Posted December 4, 2009 Sammy, if you get this running, you need to send Paul a very nice Xmas present! Quote Link to comment Share on other sites More sharing options...
JSM Posted December 4, 2009 Share Posted December 4, 2009 Are you sure your Fusible links are good? If the igintion one is bad won't this prevent power getting completely through to the ECU? http://atlanticz.ca/zclub/techtips/fusiblelinks/index.html Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted December 4, 2009 Administrators Share Posted December 4, 2009 (edited) Are you sure your Fusible links are good? If the igintion one is bad won't this prevent power getting completely through to the ECU? http://atlanticz.ca/zclub/techtips/fusiblelinks/index.html Absolutely, the fusible link in the EFI power wire off the battery is definitely suspect. s!lvias30, You said you have the '78 wiring diagram in PDF. can you send it to me? Edited December 4, 2009 by BRAAP Quote Link to comment Share on other sites More sharing options...
JSM Posted December 4, 2009 Share Posted December 4, 2009 One under this thread but it is ugly. http://forums.hybridz.org/showthread.php?t=156508 I'll keep looking Quote Link to comment Share on other sites More sharing options...
JSM Posted December 4, 2009 Share Posted December 4, 2009 I got this one from autozone. The link is better than the attachment as you can size it: http://i636.photobucket.com/albums/uu85/jeffreysm/1978_Wiring_Diamgram.gif Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted December 4, 2009 Administrators Share Posted December 4, 2009 One under this thread but it is ugly.http://forums.hybridz.org/showthread.php?t=156508 I'll keep looking Thank you for the link. I printed that one out, lied up and taped the 4 sheets together and spent some time tracing. Came up with this now. Few more questions; 1) What year is this car? Is it also a ’78? (only relevant for verifying ignition switch wiring) 2) You mentioned the ignition switch is a switch, not a key. Is that wired into the black/white wire for the ignition switch? First off, I was wrong about the plug under the dash being a 6 connector plug with only 5 wires. It is a 4 connector plug and all 4 being used. I labeled that connector on both the EFI and car side. I call this connector the umbilical as it is the umbilical connection between the car itself and EFI. Lets look closer at it. Car side of the connector; 1) The Blue wire is the RPM signal which comes directly from the ignition module/negative side of coil and tach. 2) The Green wire, (may be Green with blue stripe), will be power coming from the Fuel pump relay. That is the power for the air flow regulator. This wire should have no affect on your injectors not pulsing. 3) White wire with Red stripe, (may be white wire with black stripe), is the ignition on signal to the ECU. When the key is ON, this wire will be +12 volts telling the ECU to turn on. Be sure that wire is hot with the key on and with the key in the start position. 4) Black wire with Yellow stripe is the engine “cranking†signal, comes from the start position of the ignition switch. This tells the ECU the engine is trying to start and will enrichen the fuel as well as activate the cold start system. Verify #3 above goes +12 volt with the ignition on and key in start! That is the wire that turns on the EFI relay! (With your injectors getting power, good chance the EFI rely is energizing, but it is double pole so the other side of it that powers up the ECU could be bad, see below regarding pin #10) With the umbilical plugged back in, unplug the ECU. Verify these values at these pin locations; Pin #10 should be +12 volts when the key is ON AND in start! That is the ECU power wire directly form the EFI relay, (if the EFI relay is being turned on or is good). Based on the fact that injectors are +12v, that is good indication the EFI relay is energizing.) These pins should be earth ground; #5 #16 #17 #35 Be sure it is GOOD ground signal, i.e. no resistance! There will be a group of wire coming from the EFI harness into one eyelet that either attaches to the manifold itself or the fender well. Be sure that that ground connection is good. Also be sure the engine is grounded to the negative battery cable as well as the car body. Quote Link to comment Share on other sites More sharing options...
s!lvias30 Posted December 4, 2009 Author Share Posted December 4, 2009 Pin #10 should be +12 volts when the key is ON AND in start! That is the ECU power wire directly form the EFI relay, (if the EFI relay is being turned on or is good). Based on the fact that injectors are +12v, that is good indication the EFI relay is energizing.) ok my pin number 10 is not getting any voltage, i bought a new fuel injection main relay , These pins should be earth ground;#5 #16 #17 #35 Be sure it is GOOD ground signal, i.e. no resistance! There will be a group of wire coming from the EFI harness into one eyelet that either attaches to the manifold itself or the fender well. Be sure that that ground connection is good. Also be sure the engine is grounded to the negative battery cable as well as the car body. also yes i checked if these were grounded, and to everything you have said Quote Link to comment Share on other sites More sharing options...
s!lvias30 Posted December 4, 2009 Author Share Posted December 4, 2009 Pin #10 should be +12 volts when the key is ON AND in start! ohh , ok im ging to do that test !! Quote Link to comment Share on other sites More sharing options...
s!lvias30 Posted December 4, 2009 Author Share Posted December 4, 2009 well my pdf file of the wiring harness i got was from the fsm here is the exact link http://xenons30.com/reference.html Quote Link to comment Share on other sites More sharing options...
s!lvias30 Posted December 4, 2009 Author Share Posted December 4, 2009 Sammy, if you get this running, you need to send Paul a very nice Xmas present! YEA I KNOW!!!!!!! thanks Jeff and Paul for all the help , hopefully we can find the issue , just that I'm confused that if there is to be another "hot" wire feeding the ecu with juice then how come is not there?? well I'm off to do those step Paul have posted , gosh! its raining outside !!!! ugh Florida weather Quote Link to comment Share on other sites More sharing options...
JSM Posted December 4, 2009 Share Posted December 4, 2009 Sammy, if you looked at the diagram I posted from autozone, you will see that the EFI relay has two Fusible links going to itself. One of those may be bad. Also you should check if both green wires going into the relay have a constant 12 volts. That may be why pin 10 is not getting power. The EFI relay energizes has two different paths. Quote Link to comment Share on other sites More sharing options...
s!lvias30 Posted December 4, 2009 Author Share Posted December 4, 2009 ok Jeff i need to check that , thats a good point , if there not then change the wires??? Quote Link to comment Share on other sites More sharing options...
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