No Fuel??
#28
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hey sorry i havent posted on subject for a while, i figured it out. it ended up being the pulsation plug that comes on s4 harnesses, the s5 doesnt have them. on s4 harnesses there is only one wire out of the ecu that goes to this pulsation plug that is located in front of the passanger side tower, it takes the one injector wire and splits it into the 4 plug wires. on the s5 harness they actually did away with said plug and the wire is a hard wire all the way to the injectors. so all i did was take what was suppose to be output power from the harness and hard wired it into itself to create the correct flow of current for each injector.
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What I meant was, I see a couple grounds. I do have a ground attached near the oil filter pedestal that has a little box on it, but its not attached to anything, and I cant find anything to attach it to. Has a single spade male connector.
#31
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If it looks like a small computer chip then it is a condenser and there are two in the engine bay, one for the oil pressure sensor and one for the coils. It's not imperative whether they are bolted to the car or not. These are not a true ground. Again, you cannot visually see the main engine ground as it is hidden.
Engine ground pic: http://www.aaroncake.net/rx-7/grounding.htm
Engine ground pic: http://www.aaroncake.net/rx-7/grounding.htm
Last edited by satch; 07-30-13 at 08:50 AM.
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OH! So does this ground actually run to the ECU itself? IE, through the EM harness to the actual ECU?
*EDIT* Also, do you happen to know which ground it is coming from the ecu itself? Just need to know which one on the EM plug it is. Youve got my hopes up the Cosmo will start soon!
*EDIT* Also, do you happen to know which ground it is coming from the ecu itself? Just need to know which one on the EM plug it is. Youve got my hopes up the Cosmo will start soon!
#33
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OH! So does this ground actually run to the ECU itself? IE, through the EM harness to the actual ECU? Yes.
*EDIT* Also, do you happen to know which ground it is coming from the ecu itself? Just need to know which one on the EM plug it is. Youve got my hopes up the Cosmo will start soon!
*EDIT* Also, do you happen to know which ground it is coming from the ecu itself? Just need to know which one on the EM plug it is. Youve got my hopes up the Cosmo will start soon!
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Turns out, all those grounds are still in order, almost zero resistance from the ecu to the engine, so I think they are fine. What else would stop the injectors from firing? The car will run using starting fluid, but not of its own power. I have fuel to the rail, and back out the return, so thats not the issue.
#38
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Pin 2I (Brown/White wire) should have about 5 volts w/key to on. This is the Vref voltage which powers up certain engine sensors and it needs to read the proper voltage.
You could also have a CAS that is incorrectly stabbed and causing the timing to be out of whack which would cause the injectors to not work properly.
And are you sure you don't have the fuel lines (ingoing and outgoing) mixed up?
If you jumpered the fuel check connector and w/key to on and the return fuel hose removed and placed in a jug do you get fuel flow?
You could also have a CAS that is incorrectly stabbed and causing the timing to be out of whack which would cause the injectors to not work properly.
And are you sure you don't have the fuel lines (ingoing and outgoing) mixed up?
If you jumpered the fuel check connector and w/key to on and the return fuel hose removed and placed in a jug do you get fuel flow?
Last edited by satch; 08-24-13 at 12:39 AM.
#39
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I for sure am getting fuel back out the return line, I think Ive checked to make sure they were put on the proper way a hundred times now haha.
as far as the CAS, it was my first thought to check that, but I have absolutely zero fuel on the plugs. We are talking bone dry. Not to mention, when I run it off of starting fluid, it actually idles fairly smooth, so I think the CAS is at least not the main problem.
So the 2I plug needs power to make the injectors fire/supply the engine sensors with power? Where does the stock ecu get the 5v source from?
as far as the CAS, it was my first thought to check that, but I have absolutely zero fuel on the plugs. We are talking bone dry. Not to mention, when I run it off of starting fluid, it actually idles fairly smooth, so I think the CAS is at least not the main problem.
So the 2I plug needs power to make the injectors fire/supply the engine sensors with power? Where does the stock ecu get the 5v source from?
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I for sure am getting fuel back out the return line, I think Ive checked to make sure they were put on the proper way a hundred times now haha.
as far as the CAS, it was my first thought to check that, but I have absolutely zero fuel on the plugs. We are talking bone dry. Not to mention, when I run it off of starting fluid, it actually idles fairly smooth, so I think the CAS is at least not the main problem.
So the 2I plug needs power to make the injectors fire? If thats the case, thats the issue haha.
as far as the CAS, it was my first thought to check that, but I have absolutely zero fuel on the plugs. We are talking bone dry. Not to mention, when I run it off of starting fluid, it actually idles fairly smooth, so I think the CAS is at least not the main problem.
So the 2I plug needs power to make the injectors fire? If thats the case, thats the issue haha.
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Fell behind on this as a result of surgery and Fall matsuri. I found 5 volts on the TPS, but I couldn't find a br/w wire headed to the boost sensor. As far as the CAS, doesn't that also send the signal for the ignition? The car will run with ether, meaning the ignition is receiving signal, so shouldn't the injectors be seeing the same signal? The car was a 89 actually, S5 everything so far as I can tell.
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Well the car I pulled everything from was manufactured in 89, and it doesnt look like they changed a thing, so I would say they are the high impedance that came in series 5 fc's. How else could I tell? As far as timing, no I havent checked it yet, but the plugs are completely bone dry when I pull them out, and it never even sputters to fire. Could the timing be off enough to cause that?
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Well the car I pulled everything from was manufactured in 89, and it doesnt look like they changed a thing, so I would say they are the high impedance that came in series 5 fc's. How else could I tell? As far as timing, no I havent checked it yet, but the plugs are completely bone dry when I pull them out, and it never even sputters to fire. Could the timing be off enough to cause that?
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There isnt a resistor box, but there shouldnt be. The car it all got swapped into is an HB cosmo, thats the only model year 87 in my situation haha. The engine, ecu, and wiring are all 1990/S5. I will check the timing when I wake up tomorrow.
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Was just looking at the wiring diagram, and I noticed that when the Fuel Pump relay is on, it sends a ~5volt signal back to the ecu. I do not have a fuel pump relay wired in, as its in a totally different chassis. Could this be the issue? Does the ecu need that 5v signal to turn on the injectors?