twistedsymphony Posted August 7, 2011 Share Posted August 7, 2011 (edited) I'm helping a friend of mine get a 1978 280Z up and running, he bought it as a failed "project" from someone else, so he's never seen it run. A little background: When we started it wouldn't even turn over, I traced that to a faulty ignition relay... now it cranks but it's not getting fuel -fuel pump turns on -we have proper pressure in the lines -injectors do not fire. The injectors are new, as they were replaced by the previous owner, we could get the injectors to "click" by manually hooking them up to the battery, today I went through the harness and a copy of the FSM and verified the wiring TWICE with a multimeter so I can say without a doubt that it is correct. So that leaves me to believe that the ECM is faulty. As I said before it's a 1978, it's an Automatic and it's California Emissions (based on the fact that it has a working floor temp light) I've searched around a bunch to try to figure out what the ECM differences are year to year and all I've come up with are people claiming that the 78 is wired differently than prior years, and that the California cars make use of additional pins. But I haven't found anything that sounds concrete, nor have I found what I'm really looking for, which is the proper ECM model number for this car. I don't trust that the ECM that is currently in the car is the correct one and I'd like to know 100% what the proper ECM model number is for a 78 California Auto. Any help identifying the ECM part number for this configuration would be greatly appreciated. Thanks! Edited August 7, 2011 by twistedsymphony Quote Link to comment Share on other sites More sharing options...
HowlerMonkey Posted August 9, 2011 Share Posted August 9, 2011 If you don't have spark, it's possible the ecu is not seeing a rpm signal from the distributor which will cause it to also not fire the injectors. Also......check whether you have +12v on one of the injector terminals when the key is on. Quote Link to comment Share on other sites More sharing options...
twistedsymphony Posted August 10, 2011 Author Share Posted August 10, 2011 (edited) we ran a spark tester and we are getting spark on all cylinders. also we tested by manually squirting ether into the intake and were able to get the car to sputter. we also verified 12V at all injectors... this was one of the first things we verified, it was also covered as part of the FSM diag which we ran through twice. I'd really love to know the proper ECM Part Number so I can at least compare that to what we have. Edited August 10, 2011 by twistedsymphony Quote Link to comment Share on other sites More sharing options...
NewZed Posted August 10, 2011 Share Posted August 10, 2011 The guys at Motorsport Auto would probably help you out. They have all of the numbers and sell remanufactured ECUs and AFMs. They call the ECUs "brains" on their website. You'll probably get the best response by phone. http://www.thezstore.com/page/TZS/PROD/11-3031 Quote Link to comment Share on other sites More sharing options...
twistedsymphony Posted August 10, 2011 Author Share Posted August 10, 2011 The guys at Motorsport Auto would probably help you out. They have all of the numbers and sell remanufactured ECUs and AFMs. They call the ECUs "brains" on their website. You'll probably get the best response by phone. http://www.thezstore.com/page/TZS/PROD/11-3031 Thanks! I'll give them a shout. Quote Link to comment Share on other sites More sharing options...
z-ya Posted August 10, 2011 Share Posted August 10, 2011 I have a 78' ECM. Not sure if it's good, but you can have it for the cost of shipping. Quote Link to comment Share on other sites More sharing options...
HowlerMonkey Posted August 11, 2011 Share Posted August 11, 2011 (edited) You could send it in to blue streak for R and R or use the critical core program where you get a functioning unit returned to you. http://www.bsecorp.com/products_remanufactured_services.php You would have to do it through an auto parts store or a shop that deals with them. Also....remember that the 280zx ecu is generally not compatible. Edited August 11, 2011 by HowlerMonkey Quote Link to comment Share on other sites More sharing options...
twistedsymphony Posted August 12, 2011 Author Share Posted August 12, 2011 The guys at Motorsport Auto would probably help you out. They have all of the numbers and sell remanufactured ECUs and AFMs. They call the ECUs "brains" on their website. You'll probably get the best response by phone. http://www.thezstore.com/page/TZS/PROD/11-3031 these guys got back to me and confirmed that the proper ECM is A11-601-000, which does match what is in the car. z-ya is sending me another one to try out, Thanks! Quote Link to comment Share on other sites More sharing options...
z-ya Posted August 15, 2011 Share Posted August 15, 2011 I am sending you a A11-601-000 today. Hopefully it works for you. Pete Quote Link to comment Share on other sites More sharing options...
twistedsymphony Posted August 23, 2011 Author Share Posted August 23, 2011 Ok so first the starter wouldn't even kick on, nor would the fuel pump and I determined that the ignition relay was junk... I build a little converter harness to use modern relays and and that powered up everything in the car, the fuel pump would kick on and the engine would turn over but it wasn't getting gas. After some more testing I determined the injectors were firing because the ECU was bad so I got a new one (thanks z-ya) and after popping that in the injectors started firing... but the car still wouldn't start... So I assumed that the timing was off, after checking I realized that the plug wires were all going to the wrong points on the distributor, so I swapped those around to the proper firing order.... still wont start. as it is now it will sputter like it's going to start but never actually kicks on. -We ARE getting spark, the plugs are all new and we've used a spark tester to verify that it's getting spark. we've also loosened the adjustment bolt on the distributor and tried tweaking it but it didn't seem to make a difference. -We are getting proper fuel pressure at the rail and the injectors are firing (brand new injectors and all new fuel lines too) I have 2 ideas of what could be wrong 1. the distributor needs to be removed and re-indexed to correct the timing. 2. the AFM is toast causing the computer to produce and incorrect mixture. I'm using to working on more modern cars with MAFs and coil on plug ignitions... if anyone has any suggestions on how to reliably test the above or other things I should be looking at, I'd love to hear them... The car needs to be out of the barn it's in by this weekend so I'm sure my buddy would be happy if it drove out under it's own power instead of getting loaded on a trailer. Quote Link to comment Share on other sites More sharing options...
z-ya Posted August 23, 2011 Share Posted August 23, 2011 Did you check that you have fuel pressure and fuel flow? Quote Link to comment Share on other sites More sharing options...
NewZed Posted August 23, 2011 Share Posted August 23, 2011 Spark plug wires in the proper order for counter-clockwise rotor rotation? Quote Link to comment Share on other sites More sharing options...
Leon Posted August 23, 2011 Share Posted August 23, 2011 Did you put a timing light on the #1 plug to see if it's timed correctly instead of guessing? You can just move the spark plugs around the distributor to where #1 fires at the right spot. Makes sure to keep the firing order correct (1-5-3-6-2-4). Quote Link to comment Share on other sites More sharing options...
twistedsymphony Posted August 23, 2011 Author Share Posted August 23, 2011 (edited) Did you check that you have fuel pressure and fuel flow? yes definitely have good flow and pressure, we even checked over the diagram in the FSM to make sure all the lines were hooked up the way they should be (and they are) Spark plug wires in the proper order for counter-clockwise rotor rotation? yes, based on this image: Did you put a timing light on the #1 plug to see if it's timed correctly instead of guessing? You can just move the spark plugs around the distributor to where #1 fires at the right spot. Makes sure to keep the firing order correct (1-5-3-6-2-4). We brought a timing light but couldn't locate the mark... I'm not sure if we simply couldn't find it or if it had disappeared (the pulley is pretty rusted). Edited August 23, 2011 by twistedsymphony Quote Link to comment Share on other sites More sharing options...
rossman Posted August 23, 2011 Share Posted August 23, 2011 We brought a timing light but couldn't locate the mark... I'm not sure if we simply couldn't find it or if it had disappeared (the pulley is pretty rusted). Run your fingernail around the damper edge closest to the front cover. There is a notch where the mark is supposed to be located. Once you find the notch, put it on "0" and check that #1 is at TDC. If it is not then the damper pulley may have spun on the center hub and the timing mark is no longer where it should be located. Quote Link to comment Share on other sites More sharing options...
Leon Posted August 23, 2011 Share Posted August 23, 2011 Run your fingernail around the damper edge closest to the front cover. There is a notch where the mark is supposed to be located. Once you find the notch, put it on "0" and check that #1 is at TDC. If it is not then the damper pulley may have spun on the center hub and the timing mark is no longer where it should be located. What he said. Clean up the pulley and you should see the mark. Alternatively, you can use a piston stop. (1) Gently rotate the engine til it hits the stop, (2) mark the pulley where the pointer is pointing, (3) rotate the other way to the stop, (4) mark the pulley again. (5) Put a mark dead center in between the two that you just created and that will be TDC. Quote Link to comment Share on other sites More sharing options...
Mack Posted August 24, 2011 Share Posted August 24, 2011 I hate to say it, but I am such an advocate.... this sounds like a job for Megasquirt. With all the futzing around you've done with the wiring harness and what not, you could have installed megasquirt and had it running by now. with that being said.... here is a complete write up on how to test, adjust and verify the afm is in good shape. AFM stuff oh and an easy way to check that the dist. is in the (approximate) right position is to pop the valve cover and remove spark plug #1, turn engine until both cam lobes are pointing up in a "V" shape, and put a pencil or smething else like a long screwdriver into the #1 spark plug hole and turn the crank VERY slowly until whatever yuou put in the spark plug hole stops moving up. then remove your dist cap and check the position of the rotor. That will also tell you if your cam timing could be off, as you can verify the marks on the cam gear. Quote Link to comment Share on other sites More sharing options...
twistedsymphony Posted August 24, 2011 Author Share Posted August 24, 2011 (edited) I hate to say it, but I am such an advocate.... this sounds like a job for Megasquirt. With all the futzing around you've done with the wiring harness and what not, you could have installed megasquirt and had it running by now. I've toyed with the idea of a megasquirt setup on one of my own cars (89 Toyota pickup) but my friend who owns the Z couldn't afford it even if he wanted to... so far we've spent about $30 for the relays, and another $10 for the ECM... I also highly doubt a MegaSquirt setup would have been up and running by now since we've really only spent about 5-6 hours diaging this car tops... (granted spread out over several weeks, but still). not only that but but we'd still be having the same timing issues megasquirt or not... about the only thing it would help is getting better visibility of the AFM output... but it looks like that link you posted will help. Edited August 24, 2011 by twistedsymphony Quote Link to comment Share on other sites More sharing options...
NewZed Posted August 25, 2011 Share Posted August 25, 2011 There are a variety of ways to narrow the list of things that work and those that don't down to a manageable level. If you have confirmed that you have spark when cranking, try lining up the two lines on the distributor adjustment plates, by the locking screw. I've found that when the timing on my engine was correct, those two lines were aligned. Probably an assembly aid or done for future mechanics. Then squirt some starting fluid in the intake manifold and see if it starts. If so, you have a fuel problem, probably injectors not firing. To confirm that the wire to the ECU and the ECU operation is correct, for firing the injectors, connect a jumper wire to the negative terminal of the coil and leave the other end hanging, turn the key to On, then quick;y tap the jumper to ground multiple times. Every three times, all of the injectors should click. This trick has been described by Tony D on multiple forums, and the reason it works is described (with a little bit of extra thought) in the Fuel section of the FSM. Two simple ways to get an idea of what to focus on, fuel or spark. You said that you knew you had both, but you might as well confirm separately. If your injectors are opening and the engine doesn't start, then you should have wet, gassy spark plugs. Even without injectors, I believe that your CSV should be dumping enough gas to get it to kick. The ignition relay sends power to many different places, maybe you missed one with your converter harness. As for your timing, put the car in high gear and slowly roll it while shining a light on the crank pulley. You'll find the notch. Then mark and while you're down there, clean up the timing tab and mark Zero with some paint. These engines are just a collection of simple devices. Just make each one do what it's supposed to do and you'll have a running engine. Just dumping a few thoughts out there... Quote Link to comment Share on other sites More sharing options...
twistedsymphony Posted August 25, 2011 Author Share Posted August 25, 2011 (edited) Squirt some starting fluid in the intake manifold and see if it starts. If so, you have a fuel problem, probably injectors not firing. Granted it didn't "run" (it just sputtered and popped) but that is exactly the method used to confirm we were having a fuel problem before I created this thread. To confirm that the wire to the ECU and the ECU operation is correct, for firing the injectors, connect a jumper wire to the negative terminal of the coil and leave the other end hanging, turn the key to On, then quick;y tap the jumper to ground multiple times. Every three times, all of the injectors should click. This trick has been described by Tony D on multiple forums, and the reason it works is described (with a little bit of extra thought) in the Fuel section of the FSM. this is exactly the method used to determine that the ECU was bad and lead me to creating this thread. After replacing the ECU we confirmed that the injectors worked because we could hear them click, the car sputters just like it did when we squirted ether into the intake with the dead ECU and the spark plugs are getting soaked with fuel. The ignition relay sends power to many different places, maybe you missed one with your converter harness. doubtful: The relay had 6-pins and a grounding plate, my replacement has 6 pins and a grounding loop. I confirmed that everything on the fuse panel that was originally non-functionaly due to the bad ignition relay became functional after replacing it. I didn't splice anything, or develop some complicated nest of wires, I literally made and adapter that let you plug in modern relays in place of the old expensive metal ones. As for your timing, put the car in high gear and slowly roll it while shining a light on the crank pulley. You'll find the notch. Then mark and while you're down there, clean up the timing tab and mark Zero with some paint. The car is an automatic so I don't have much control over what gear it's in, it's also in a barn at the bottom of a hill... so the only way it's rolling is under it's own power or with a winch. I'm thinking i'll probably just pull the belts and wire brush it until I can find the mark. and mark it with white out Edited August 25, 2011 by twistedsymphony Quote Link to comment Share on other sites More sharing options...
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