Posted May 15, 20168 yr comment_495055 1976 280Z. Car was given to us. Engine just rebuilt and put back in. Getting spark. Fuel pump replaced with known good unit (parts car that ran). Dropping resistors measure 6 ohms per troubleshooting guide. Relays replaced #2 injector does not measure 12V at ECU (all others do) brand new fuel filter i have pressure at the rail (loosen hose clamp and fuel sprays out). spark plugs are not wet when removed. i suspect that the injectors are not opening timing could be off as I did the rebuild myself brand new battery. car turns over, does not start. any ideas? Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/ Share on other sites More sharing options...
May 15, 20168 yr comment_495071 Are all the EFI connections plugged in, the one off the battery mainly, and the grounds cleaned? The ECUs sole purpose is controlling the EFI, maybe it's bad and the reason you got it for free? Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/#findComment-495071 Share on other sites More sharing options...
May 15, 20168 yr comment_495073 As it turns over, does it try to crank at all? The timing could be off? Pull a hose off the intake and squirt some starting fluid in there and see if it hits. Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/#findComment-495073 Share on other sites More sharing options...
May 15, 20168 yr comment_495090 The ECU opens the injectors based on what it sees on the blue wire from the coil negative to the ECU Pin #1. You can test that circuit by connecting a wire to coil negative and tapping it to ground with the key On. Every tap should cause a spark from the coil and every third tap will case the injectors to click. You can also test continuity to coil negative from Pin 1 before getting crazy with jumper wires. Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/#findComment-495090 Share on other sites More sharing options...
May 16, 20168 yr Author comment_495178 Double checked all EFI connections - appear connected. Tried starting fluid after the AFM, no luck. Since I have a parts car (that ran), I will try ECU swap next. Next I'll check the clicking of the injectors - need my son there to turn the key. Thanks for the help. Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/#findComment-495178 Share on other sites More sharing options...
May 16, 20168 yr comment_495182 One of the simplest things that you can do is to check continuity between the coil's negative terminal and Pin 1 of the ECU connection. You'll have the connector sitting in front of you before you can even take the ECU out. But not starting with starting fluid is a significant sign that you're not getting proper spark. Starting fluid (the real stuff, not WD-40 or brake fluid) is very flammable. If the engine won't at least pop a few times then it's not getting to where the spark is, or there's no spark under cylinder pressure. I wouldn't do any fuel related stuff until I got a few pops with starting fluid. Remove one of the hose to the intake manifold and squirt fluid directly into the manifold. Ignition is a completely separate thing from fuel. Also, you're not really "showing your work" (like math class). You said "appears connected" which could mean that you just eyeballed a few things. That's not good enough. C-. Edited May 16, 20168 yr by Zed Head Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/#findComment-495182 Share on other sites More sharing options...
May 16, 20168 yr Author comment_495187 some of the clips on the fuel injectors were missing and I replaced those and insured they were snapped in place. I did touch each one of the connectors to verify connection. I did use real starting fluid also. will go into the manifold directly. I did get one pop, but that was it. I haven't run a continuity check from the coil's negative wire to the ECU bc I thought I had to actually run a wire with an alligator clip to the inside of the car to get close enough to pin 1. Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/#findComment-495187 Share on other sites More sharing options...
May 16, 20168 yr comment_495191 With the key off, you can connect a jumper wire from the coil negative to ground, Then check Pin 1's continuity to ground. If Pin 1 shows continuity, then there's a complete circuit. Or, you can just check for voltage at Pin 1 with the key On. Power will pass from the battery through the coil to the negative terminal and down the circuit to Pin 1. Use the Fuel Injection Guide to make sure you're measuring Pin 1. Edited May 17, 20168 yr by Zed Head Changed download to classiczcars.com Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/#findComment-495191 Share on other sites More sharing options...
May 16, 20168 yr comment_495198 If you are not getting any response from starter fluid, you must have a problem with spark or it's flooded and the spark plugs are so wet they wont spark. How did you check spark? Your saying "Getting spark", but not explaining how you came to that conclusion. Explaining what you did step by step can give clues for others to give you better help and advice. You could have a bad connection or bad TIU. I would concentrate on that first. You should get some sort of response from starter fluid. You think the injectors are not opening which could also indicate no signal from pin 1, coil trigger. Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/#findComment-495198 Share on other sites More sharing options...
May 16, 20168 yr Author comment_495209 I pulled several different plugs to check if they were wet and to check spark. Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/#findComment-495209 Share on other sites More sharing options...
May 17, 20168 yr comment_495212 Were they black from soot? You may need to clean or replace the plugs. What gap are you at? I think 36 to 40 is good. Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/#findComment-495212 Share on other sites More sharing options...
May 17, 20168 yr Author comment_495216 Brand new Bosch spark plugs Link to comment https://www.classiczcars.com/forums/topic/55469-wont-start/#findComment-495216 Share on other sites More sharing options...
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