scooterhulk Posted November 18, 2013 Share Posted November 18, 2013 I have a thin sheet of rubber wrapped around my coil, between the coil and the coil bracket. Is this a problem? Because I'm not getting spark right this second, and I think the coil is good. I've got an Accel Super Stock 8140c with 1.6 ohms on the primary and 7.05k at the secondary, which I believe is within range (definitely for the primary, pretty sure for the secondary) I can't remember exactly why I put that piece of rubber in there at the moment. I think it was because I had moved the coil bracket mounting location and noticed that the bracket wasn't tight enough to clamp around the coil. I'm getting the impression that the coil should be in direct contact with the mounting bracket, grounding it to the chassis. Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted November 18, 2013 Share Posted November 18, 2013 The coil does not conduct through the case. You should have 3 connections, the (+) and (-) and the high voltage tower. As long as those are connected, the coil should work. Quote Link to comment Share on other sites More sharing options...
scooterhulk Posted November 18, 2013 Author Share Posted November 18, 2013 (edited) Okay. Thanks. Could you tell me if the secondary resistance is acceptable? Edited November 18, 2013 by scooterhulk Quote Link to comment Share on other sites More sharing options...
scooterhulk Posted November 19, 2013 Author Share Posted November 19, 2013 (edited) I imagine this coil is probably good. I'm only getting 5.6 volts to the positive terminal. Fuel pump will kick on when it's hooked up, Thoughts? Edited November 19, 2013 by scooterhulk Quote Link to comment Share on other sites More sharing options...
NewZed Posted November 19, 2013 Share Posted November 19, 2013 I imagine this coil is probably good. I'm only getting 5.6 volts to the positive terminal. Fuel pump will kick on when it's hooked up, Thoughts? You have this car, engine and Megasquirt and you're wondering if the coil needs to have the case grounded to get a spark? - 77 280z - L28et, Megasquirt MS1v3 5.6 volts at the positive, if you had 12 at the battery, is a sign that you have current flow on that circuit. The fuel pump running is not a good sign. You have an error somewhere, and it looks like a long road ahead to figure it out. http://www.msextra.com/doc/index.html#ms1 Quote Link to comment Share on other sites More sharing options...
scooterhulk Posted November 19, 2013 Author Share Posted November 19, 2013 (edited) According to the wiring diagram on DIY Autotune, the + side of the coil connects to the fuel pump, which is why I mentioned it. So, when I complete the circuit the fuel pump kicks on. In reference to your comment, I had this MS professionally installed 5 years ago. Have never had any problem out of it. I did some work on this car that had it out of commission for awhile. One of the things I did was the maxi-fuse upgrade, and while freshening up the car I found a bad connection on the ground for the coil. I had previously thought I had the coil was dying on me. So, I fixed the connection. I cut the wire under the passenger seat for the fuel pump but reconnected it after my floor work was done. Edited November 19, 2013 by scooterhulk Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted November 19, 2013 Share Posted November 19, 2013 Okay. Thanks. Could you tell me if the secondary resistance is acceptable? The resistance measurements you listed look acceptable. Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted November 19, 2013 Share Posted November 19, 2013 I imagine this coil is probably good. I'm only getting 5.6 volts to the positive terminal. Fuel pump will kick on when it's hooked up, Thoughts? Sounds like a wiring error. If you have 12V to the + of the coil, and it drops to 5.6 with the pump on, you have undersized the wires to the coil and the pump or you have a bad relay powering it. I am hoping you DO have this circuit switched by a relay. I do not think your pump should run just because you have 12V to the hot lead, ideally the pump is on a separate relay controlled by the computer, so it can prime the system with ignition on, and only run the pump continuously if you have the engine running. Quote Link to comment Share on other sites More sharing options...
scooterhulk Posted November 19, 2013 Author Share Posted November 19, 2013 I do not have 12v going to the coil. I have 5.6, and the FP runs when the coil is connected. But I do not have 12v that drops to 5.6. It is only 5.6. Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted November 19, 2013 Share Posted November 19, 2013 I do not have 12v going to the coil. I have 5.6, and the FP runs when the coil is connected. But I do not have 12v that drops to 5.6. It is only 5.6. I am not following you. If you wired to the MS1 V3 diagram you should have battery voltage at your pump when the relay is on. The coil positive is connected to a different circuit, but should also have battery voltage. If you have 12V at your battery, that same voltage should be at your pump and coil. Now if you measure 5.6V at the pump when it runs, the pump is drawing too much current for the wiring or you have a bad relay. I am confused when you say the pump only runs with the coil connected. Where is the coil negative wired? I assume you have an electronic ignition unit, but maybe you are dropping battery voltage with a ballast resistor and a points type ignition? You are not saying you have a 5.6V battery? More information is needed. Quote Link to comment Share on other sites More sharing options...
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