ModernS30 Posted October 18, 2010 Share Posted October 18, 2010 Ok guys, I don't know why, I fail at finding anything on this. I found something a long time ago and I can't find it anymore. I have a Condenser that was damaged during my engine transfer. It has 2 wires, in and out, goes the the distributor from the body harness. Now, I remember reading that is sets the pulse for the injectors. This may or may not be true but I am not getting injector pulse. I have been going through things and it could possibly be this condenser. I would get a picture but I don't actually know where the thing went. If anybody knows what I am talking about or has any information that would be fantastic. Its on a 1977 280z. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 18, 2010 Share Posted October 18, 2010 No, a condenser is a noise suppression device. If you don't have an injector pulse, do you have a spark pulse? If the coil is not being switched, the injectors will not fire. The ECU requires 3 pulses on the coil negative to pulse the injectors once. With power "on" simply tapping the negative of the coil to ground and producing a spark will trigger the injectors. Every third tap the injectors should click (if you are getting a spark, use a decent ground!) People forget that if the distributor goes TU, the injection system won't work. It shouldn't. No spark means no fuel. That is a safety device for a crash stall. Earlier cars used an AFM interlock to stop the fuel pump, later cars used an oil pressure switch. That way in an accident when it stalls, the lack of a spark pulse kills the injectors from flooding the engine, and lack of airflow or oil pressure stops the fuel pump in case there's a broke fuel line causing a gas spill and immolation of the occupants and a ghastly and malodorous Car-B-Que. Mmmmm, "Long Pig Roasting" quipped our guide as we trekked the Kokoda Trail. We looked forward to supping on this mythical creature we had heard so much about. Wew turned the corner and were confronted by tribesmen all holding spears and... Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 18, 2010 Author Share Posted October 18, 2010 No, a condenser is a noise suppression device. If you don't have an injector pulse, do you have a spark pulse? If the coil is not being switched, the injectors will not fire. The ECU requires 3 pulses on the coil negative to pulse the injectors once. With power "on" simply tapping the negative of the coil to ground and producing a spark will trigger the injectors. Every third tap the injectors should click (if you are getting a spark, use a decent ground!) People forget that if the distributor goes TU, the injection system won't work. It shouldn't. No spark means no fuel. That is a safety device for a crash stall. Earlier cars used an AFM interlock to stop the fuel pump, later cars used an oil pressure switch. That way in an accident when it stalls, the lack of a spark pulse kills the injectors from flooding the engine, and lack of airflow or oil pressure stops the fuel pump in case there's a broke fuel line causing a gas spill and immolation of the occupants and a ghastly and malodorous Car-B-Que. Mmmmm, "Long Pig Roasting" quipped our guide as we trekked the Kokoda Trail. We looked forward to supping on this mythical creature we had heard so much about. Wew turned the corner and were confronted by tribesmen all holding spears and... If you don't have an injector pulse, do you have a spark pulse? Yes, I have spark. Mmmmm, "Long Pig Roasting" quipped our guide as we trekked the Kokoda Trail. We looked forward to supping on this mythical creature we had heard so much about. Wew turned the corner and were confronted by tribesmen all holding spears and... What? What I had read in a previous thread I can not find anymore is that the condenser somehow controlled the pulse of the injectors? I am fairly certain with what you have told me this is not true. I was aware that the oil pressure switch would kill the fuel pump. The pump is running. I have fuel pressure, I have spark, I do not have injectors opening. Somewhere I am losing the signal. The injectors fire off the ground, I know this. The car will fire off starter fluid. I have visual and the noise from a spark arc with the wire off the plug and arcing to the chassis of the car. I have fuel pressure in the fuel rail. The only thing absent to my car running is the injectors opening. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 18, 2010 Share Posted October 18, 2010 The methodology to test injector pulse was given. No test was performed or results logged just more statements. Given your statements, in the absence of testing as suggested, you have a bad input circuit on the ECU and need to replace it. I know this likely isn't the proper answer, but with what you are giving me to work with, it is the only logical conclusion. Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 18, 2010 Author Share Posted October 18, 2010 The methodology to test injector pulse was given. No test was performed or results logged just more statements. Given your statements, in the absence of testing as suggested, you have a bad input circuit on the ECU and need to replace it. I know this likely isn't the proper answer, but with what you are giving me to work with, it is the only logical conclusion. I am confused by what you are saying I think. Do you mean to test the injectors I ground the negative of the coil 3 times and the injectors should click? Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 18, 2010 Author Share Posted October 18, 2010 Ok, Tony, upon trying to ground it out. I could not even get a spark off the negative coil post. When I tried this I noticed smoke coming from the ignition resistor on the coil bracket. Upon further inspection that larger of the 2 resistors in there was glowing red not. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 18, 2010 Share Posted October 18, 2010 (edited) after much waiting and apparently a site crash: "If the coil is not being switched, the injectors will not fire. The ECU requires 3 pulses on the coil negative to pulse the injectors once. With power "on" simply tapping the negative of the coil to ground and producing a spark will trigger the injectors. Every third tap the injectors should click (if you aren't getting a spark, use a decent ground!)" I don't know how to put that much clearer. If you are simply tapping the wire from the negative post on the coil to ground and resistors are glowing red hot and you are smelling smoke something is FUBAR in your setup and you've neglected to inform us of modifications or something along those lines. Tapping of the negative side of the coil with power applied to the postivie side is electrically the same as the gating action of the transistor ignition unit, save for the capacitor discharge that gives the initial coil saturation. If you were getting spark cranking the car, this test simulates that without all the noise so you can hear the injectors click every third event (or see the noid light flash...) This should precipitate nothing different than cranking the car. If things are glowing red hot and smoking, you got serious problems. I don't know what 'getting spark off the negative coil post' is supposed to mean---I don't know where that came from, it wasn't in the instructions given, and I have no frame of reference for what it's relevance is supposed to be. There should be a blue-white spark out of the coil wire directed to a ground of at least 0.25" If it pops, every third pop should preceipitate a click from the injectors. Did you hook up the wire that senses negative on both ends (blue wire separate from the harness at the ECU and hooks to the coil negative post?) Edited October 18, 2010 by Tony D Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 18, 2010 Author Share Posted October 18, 2010 I am positive that my issue has something to do with the condenser. The blue wire goes to - and the white/black to the positive? The wire that the condenser goes in also smokes. I am pretty sure something is way fubar. The only modification I have is a Blaster 2 coil, the old coil had gone bad. The injectors are replacement units, supposed to be stock. I tried your tapping thing, It doesn't do anything. I tried to grounded to the freaking - battery terminal and everything. Quote Link to comment Share on other sites More sharing options...
mario_82_ZXT Posted October 18, 2010 Share Posted October 18, 2010 If you think the condensor is bad shouldn't you be able to run without it? It's a noise suppression device, I think it's a cap right? Are you running a ballast resistor? Is your coil for a ballast ignition? If you have spark but no fuel check to see if your injectors have 12v and that the ECU has power when the key is on and cranking. Also check to see if the ECU is properly grounded. There's a wire that runs along the top of the firewall that has 3 blue and 1 black wire, that is the injector and ECU ground. Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 18, 2010 Author Share Posted October 18, 2010 If you think the condensor is bad shouldn't you be able to run without it? Well, the condenser had a wire ripped off. I was running without it. The wire got super hot and started smoking. It's a noise suppression device, I think it's a cap right? Not sure? Are you running a ballast resistor? Is your coil for a ballast ignition? It has the resistor, that is the one that was getting super hot. Do you think I should bypass this? If you have spark but no fuel check to see if your injectors have 12v and that the ECU has power when the key is on and cranking. Also check to see if the ECU is properly grounded. There's a wire that runs along the top of the firewall that has 3 blue and 1 black wire, that is the injector and ECU ground. I believe that is grounded but I will double check. The injectors have power, remember L-jetronic fires off the grounds. So I am assuming it is a grounding issue somewhere. Just having no pulse I was wondering if it could have been something else. Quote Link to comment Share on other sites More sharing options...
Pharaohabq Posted October 18, 2010 Share Posted October 18, 2010 Yes the Condenser shoudl just be a Cap. Basically it just evens out the noise generated by your spark discharges to eliminate noise on your radio. It really sounds to me like there's a ground that's not connected right. you shouldn't be getting burning anything wirewise. Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 18, 2010 Author Share Posted October 18, 2010 I am fairly certain this car is totally jacked wiring wise. I do not know how. If I unplug the wire that is supposed to have the condenser in it I have no issue with smoke or glowing hot wires. Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 19, 2010 Author Share Posted October 19, 2010 I am fairly certain this car is totally jacked wiring wise. I do not know how. If I unplug the wire that is supposed to have the condenser in it I have no issue with smoke or glowing hot wires. I don't care what anybody says anymore. I have 100% determined that the condenser has something to do with it. I do not have the condenser, but when the wires where the condenser plug in are plugged together, key in the on position, the ballast resistor glows red hot. I can also not get the - post on the coil to ground out. If I un plug the wires, I can ground out the negative post on the coil, but it will not make the injectors click, no matter how many times in a row I do it. I have spark at the plugs. I have fuel in the rail. It is obvious the injectors are not opening. I have a feeling the condenser is required. Quote Link to comment Share on other sites More sharing options...
mario_82_ZXT Posted October 19, 2010 Share Posted October 19, 2010 (edited) Dude... You've bypassed the condensor by connecting it straight to ground? You've just created a short. The only reason something hasn't caught fire yet is because your ballast resistor is doing the current limiting. I think one of your fusible links might not be a real one because I'm pretty sure those wires pass through one and it should have blown by now. Just disconnect the wire that goes through the condensor and tape off the end. Edited October 19, 2010 by mario_82_ZXT Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 19, 2010 Share Posted October 19, 2010 "I don't care what anybody says anymore. I have 100% determined that the condenser has something to do with it. " Man, I'm so glad I don't have to try anymore. Good luck with that! Let somebody know when it's fixed just don't do it every step of the way, wait until it's fixed and give us all the condensed version. Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 19, 2010 Author Share Posted October 19, 2010 Dude... You've bypassed the condensor by connecting it straight to ground? You've just created a short. The only reason something hasn't caught fire yet is because your ballast resistor is doing the current limiting. I think one of your fusible links might not be a real one because I'm pretty sure those wires pass through one and it should have blown by now. Just disconnect the wire that goes through the condensor and tape off the end. This condenser has 2 plugs and plugs to the distributor from the body harness (engine room per FSM). My fusible links have the maxi-fuse swap. Running 30 30 50 80. 80 is for the upgraded alternator. Everything I am running is per write up and what I was told to do. Quote Link to comment Share on other sites More sharing options...
mario_82_ZXT Posted October 19, 2010 Share Posted October 19, 2010 Look up how a cap works for noise suppression. You put it across the load in a high impedance circuit to suppress high frequency noise. If you connect the 2 leads that it has together, you are basically shunting the circuit straight to ground (aka a short). Like I said before, the reason something hasn't caught fire yet is because your ballast resistor is limiting the current. If your condensor is broken and you don't want to get another, tape off the end that goes to the harness and remove the grounded end. I would also check your ballast resistor as you might have damaged it from putting so much current through it. Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 20, 2010 Author Share Posted October 20, 2010 I have tried to find a new condenser for the one that was damaged and could not. I got the car running. A few stupid mistakes with the wiring. Sorry I am human, thanks for any and all help! Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 20, 2010 Share Posted October 20, 2010 So then the condenser was NOT related to the injectors opening and closing... Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 20, 2010 Author Share Posted October 20, 2010 So then the condenser was NOT related to the injectors opening and closing... Not at all. I am still worried about it though. (Call me a jackass it is 100% fitting ) I don't think I should be running without it. It plugs to the dizzy. Quote Link to comment Share on other sites More sharing options...
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