Crow's '76 Posted September 20, 2009 Share Posted September 20, 2009 So I have a 1976 280Z and one of the previous owners DIY'd an alarm system using about 9 thousand wire splices and 4 different relays. I've gotten the alarm out it seems, but for some reason I'm getting no injector pulse. I've had a friend mechanic over to take a look but he can't figure out why I'm getting no injector pulse. I've looked for threads of this nature but didn't find any useful info. I need to get rid of this car asap and I'd appreciate it if anyone had any input, thanks ahead of time guys Quote Link to comment Share on other sites More sharing options...
hoov100 Posted September 20, 2009 Share Posted September 20, 2009 check that your ECU is getting power, check your fusible links and fuses. Quote Link to comment Share on other sites More sharing options...
Crow's '76 Posted September 21, 2009 Author Share Posted September 21, 2009 Checked the fuseable links, they have power to all the points, the fuses seemed okay but I will check again, from what I can tell they're all relaying power but still no injector pulse.. Quote Link to comment Share on other sites More sharing options...
hoov100 Posted September 21, 2009 Share Posted September 21, 2009 try disconnecting the ECU plug, blow out the connection and plug it back in. It sounds crazy, but has actually worked a few times. Quote Link to comment Share on other sites More sharing options...
PhilbertZ Posted September 21, 2009 Share Posted September 21, 2009 try disconnecting the ECU plug, blow out the connection and plug it back in. It sounds crazy, but has actually worked a few times. interesting....I'm in the middle of diagnosing my failed smog and running tons of FSM tests using a voltmeter/ohmmeter, and my number 5 injector returns no voltage when tested at the ECU...wonder if this is part of issue - if I need to "blow out" the ECU harness hole there? Or, are there other common reasons that only 1 injector would return a "0" voltage read (I'm running rich, not lean, so I'm thinking this isn't part of my smog problem...)? Quote Link to comment Share on other sites More sharing options...
hoov100 Posted September 21, 2009 Share Posted September 21, 2009 All I know for that, is thats its saved me and a few random people stuck on the side of the road, who's injectors "quit working" Quote Link to comment Share on other sites More sharing options...
Tennesseejed Posted September 22, 2009 Share Posted September 22, 2009 To troubleshoot OE FI you have to use the EFI Bible http://forums.hybridz.org/showthread.php?t=135748 Crow, if you are not getting an injector pulse you first need to check if you are getting 12V on ECU Pin 1 with the ignition on. Go from there through the troubleshooting tests in the EFI Bible. If you are not getting 12V on ECU Pin 1 then your coil is not getting voltage from the ignition control unit (ICU). The testing procedure for the ICU is found in the FSM. I pulled an alarm system, a RF booster and a stereo installation that epitomized the definition of sub-saharan engineering out of my Z when I bought it. I've been down the road your on. Use the manuals available and keep working on it. Philbert, same for you. You mention using the FSM and a multimeter so you are certainly on the right track. Looking at the EFI schematic, both injector 5 and 6 share the same circuit. I.e., If injector 6 is getting power, then injector 5 should as well. Do the test for injector 5 on page 65. If you are not getting 12V on ECU pin 30 with the ignition on, then you have a short in your circuit. Then its just a matter of testing continuity until you find the break. Good luck. Quote Link to comment Share on other sites More sharing options...
hoov100 Posted September 22, 2009 Share Posted September 22, 2009 To troubleshoot OE FI you have to use the EFI Bible thats more of opinion then fact, these EFI systems are simple and easy to learn. I would consider the EFI bible a good reference book for new guys who know nothing of EFI systems or how they work. 80% of all problems i have found on EFI s30's s130's and z31's where just corroded connectors, or the AFM. Quote Link to comment Share on other sites More sharing options...
PhilbertZ Posted September 22, 2009 Share Posted September 22, 2009 To troubleshoot OE FI you have to use the EFI Bible http://forums.hybridz.org/showthread.php?t=135748 Philbert, same for you. You mention using the FSM and a multimeter so you are certainly on the right track. Looking at the EFI schematic, both injector 5 and 6 share the same circuit. I.e., If injector 6 is getting power, then injector 5 should as well. Do the test for injector 5 on page 65. If you are not getting 12V on ECU pin 30 with the ignition on, then you have a short in your circuit. Then its just a matter of testing continuity until you find the break. . Thanks! I printed out the EFI bible a couple months ago (whe I failed smog and knew nothing about EFI) and have been using it to learn about and test my EFI system (though some of the tests are different in my 1980ZX specific FSM - so I did the FSM tests too). I'll try that test you recommend - but I'll also try blowing out the ECU plug to see if that's got dsut in it, blocking the circuit Quote Link to comment Share on other sites More sharing options...
Crow's '76 Posted September 25, 2009 Author Share Posted September 25, 2009 Hey guys thatnks for all the help, for some reason I seem to be missing a fusible relay...looks like they just cut the plastic connector off cause the cable is almost too short to reach. Anyway she's started up and is runnin again, thanks for all the help! Quote Link to comment Share on other sites More sharing options...
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