mclarenross Posted June 10, 2014 Author Share Posted June 10, 2014 yeah 1JZ, I've asked my mechanic mate Rory to have a look at this thread, to get his input... I'll update soon. Quote Link to comment Share on other sites More sharing options...
Shane Posted June 10, 2014 Share Posted June 10, 2014 yeah 1JZ, I've asked my mechanic mate Rory to have a look at this thread, to get his input... I'll update soon. OK well to get you going and to check out what you have, it's still a pretty easy process to rig something together, despite any wiring differences. Feed a decent 12v feed to the white wire of your resistor pack, and connect the black wires from the pack to each injector, leaving the original 12v feeds disconnected for now. The other side of the injectors need to go back to pins 8, 9 and 10 of plug C88 of the ECU but make sure you observe the pairing as in the links. You do need to check that all of the cables you have cut so far are 100% the feeds to the injectors though, this bit concerns me a bit, but is easy to check. I am worried if not you may have lost a 12v feed to something else. When you have done all this, another check you should do is to measure the voltage of the 5v leg of your map sensor, but use the negative terminal of your battery for your gnd connection (that last bit is important), if you have anything other than 5.0 volts on that there are other problems we will need to look at too. Good luck. Quote Link to comment Share on other sites More sharing options...
mclarenross Posted June 15, 2014 Author Share Posted June 15, 2014 (edited) Hi our problem at moment is ,engine will not fire via resistor pack with each wire from resistor going to each injector individually , but if you put feed to injectors without resistor it will fire but run rough, our maths at moment are resistor pack 6.7ohms,and injectors 2.5ohms, giving current reading of 1.3amps , original reading without resistor and 13ohms injectors was 0.9amps , will ecu work reading 1.3?? Edited June 16, 2014 by mclarenross (see edit history) Quote Link to comment Share on other sites More sharing options...
Shane Posted June 15, 2014 Share Posted June 15, 2014 Hi our problem at moment is ,engine will not fire via resistor pack with each wire from resistor going to each injector individually , but if you put feed to injectors without resistor it will fire but run rough, our maths at moment are resistor pack 6.7ohms,and injectors 2.5ohms, giving current reading of 1.3amps , original reading without resistor and 13ohms injectors was 0.9amps , will ecu work reading 1.3????? If the original injectors were high impedance you must run the resistors with the low impedance injectors, the injector driver transistors in the ECU will not be able to handle the extra current for long. If you have the resistor in series with the live side of the injector and ground the other side can you hear/feel the injector open? You should hear a click from the injector and if you put your finger on it feel it also. Quote Link to comment Share on other sites More sharing options...
David P Posted June 15, 2014 Share Posted June 15, 2014 You might find this/these links handy. http://www.mkivsupra.net/vbb/showthread.php?309161-N-A-to-1JZ-GTE-What-s-involved&p=3886614&viewfull=1#post3886614 http://www.mkivsupra.net/vbb/group.php?groupid=62 Quote Link to comment Share on other sites More sharing options...
mclarenross Posted June 15, 2014 Author Share Posted June 15, 2014 its really doing my head in now, if I had a match and some petrol close by I think the supra might be on fire right now. Yeah we've wired the 6 black injector wires into the live feed above the individual injectors, but it just won't fire, we go back to the old configuration for running the 440 high imp injectors and it fires straight up... ( I the it off straight away)I think are the injectors not working, but they fire up with the old configuration, could it be the resistor pack, but it was fine when it cameout of driftbears car and it sounds like its putting out the right numbers, cant be a bad earth as it works on the 440 set up. We've checked all the wiring to make sure all the connections are good, Arghh this car!!! Thanks David for the post, not quite sure what your links can help me with, is it the coil packs that you think could be wrong? Quote Link to comment Share on other sites More sharing options...
David P Posted June 15, 2014 Share Posted June 15, 2014 Just handy links to 2J-GE & 1J-GTE electrickery that might be handy, I can't help more, yet understand your pain. Quote Link to comment Share on other sites More sharing options...
mclarenross Posted June 15, 2014 Author Share Posted June 15, 2014 Just handy links to 2J-GE & 1J-GTE electrickery that might be handy, I can't help more, yet understand your pain. Thanks David, I'll keep pluging away! Quote Link to comment Share on other sites More sharing options...
David P Posted June 15, 2014 Share Posted June 15, 2014 (edited) could it be the resistor pack, The resistor pack has 6 resistors and 7 wires, 1 of them is a common return and is the only possible fault it could have to cause it not to fire on any cylinder. Edited June 16, 2014 by David P (see edit history) Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 16, 2014 Share Posted June 16, 2014 Have you followed Shane's instructions, in both his posts above, word for word? That is the correct way to diagnose this issue and is what any competent garage familiar with EFI would do, unless they jumped straight in with a `scope and a current clamp on the injector feeds. Quote Link to comment Share on other sites More sharing options...
mclarenross Posted June 16, 2014 Author Share Posted June 16, 2014 hi Chris, Yeah we've followed Shanes instuctions to the tee, its really strange, I'm thinking I'm going to buy some individual resistors from RS components today (RS HS50 6R8 50W) and try wiring them individually... David, why do you think it could be the common return? when you say return, do you mean earth? I thought the common wire was bringin the live feed into the resistor pack? from the ecu side? Quote Link to comment Share on other sites More sharing options...
Shane Posted June 16, 2014 Share Posted June 16, 2014 hi Chris, Yeah we've followed Shanes instuctions to the tee, its really strange, I'm thinking I'm going to buy some individual resistors from RS components today (RS HS50 6R8 50W) and try wiring them individually... David, why do you think it could be the common return? when you say return, do you mean earth? I thought the common wire was bringin the live feed into the resistor pack? from the ecu side? Yes, it should be. So what happens when you ground the other side of the injector when there is 12v getting to it via the resistor? TBH, not a lot can go wrong with a wire wound resistor, so I wouldn't rush out and buy them yet. Also, for test purposes, just about any low value resistors will work initially. On David's car we used 2 x 13 ohm 1 watt carbons in parallel (6R5) just to get it going. Quote Link to comment Share on other sites More sharing options...
mclarenross Posted June 16, 2014 Author Share Posted June 16, 2014 Yes, it should be. So what happens when you ground the other side of the injector when there is 12v getting to it via the resistor? Hi Shane, im not quite sure what you mean? we haven't touched the ground side of the injectors, so they should just run to the ecu as they did before... are you suggesting I try a different ground? thanks Quote Link to comment Share on other sites More sharing options...
Shane Posted June 16, 2014 Share Posted June 16, 2014 Hi Shane, im not quite sure what you mean? we haven't touched the ground side of the injectors, so they should just run to the ecu as they did before... are you suggesting I try a different ground? thanks In a previous post I told you what pins of the ecu were used, you could unplug the ecu from there and ground those 3 pins in turn, as you ground them you should hear 2 injectors fire. That's different to a 2j, where they each go back to their own pin so you would do it 6 times, but you get the idea? Assuming you hear the injectors fire then you can assume the 12v feed to the injectors and the resistor pack is ok and we can move on, it would also prove the wiring back to the ECU, although the fact it runs without the resistors seems to suggest that side is fine anyhow. I wish you were closer and I think we could clear this up quite quickly, but you are miles away. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 16, 2014 Share Posted June 16, 2014 If the 1JZ harness is the same as a 2JZ there should be two eyeletted earths for the ecu connected to bolt holes on the bottom of the intake runners. They are VERY hard to see, yoo meed a mirror, or feel for them. they often get left off. They go back to two of the ecu pins, maybe more than two. With one or both disconnected you will get some very odd faults. one is often the engine management light is on VERY dimly all the time, or does not work at all. Find them, make sure they are both soundly connected. undo them and re tighten them. You could disconnect the plugs at the ecu and check the relevant ground pins at the PLUG are connected to ground using a continuity tester function on your multi meter, as well as physically finding them at the engine and checking them mechanically and visually. I am away tomorrow, but later I can take a photo of a set of runners off an engine and indicate where they should bolt to on a 2JZ. I suspect a 1JZ will be the same though. Quote Link to comment Share on other sites More sharing options...
David P Posted June 16, 2014 Share Posted June 16, 2014 I can help with that bit. The black wires in centre of pic are ECU grounds. Quote Link to comment Share on other sites More sharing options...
Shane Posted June 16, 2014 Share Posted June 16, 2014 If the 1JZ harness is the same as a 2JZ there should be two eyeletted earths for the ecu connected to bolt holes on the bottom of the intake runners. They are VERY hard to see, yoo meed a mirror, or feel for them. they often get left off. They go back to two of the ecu pins, maybe more than two. With one or both disconnected you will get some very odd faults. one is often the engine management light is on VERY dimly all the time, or does not work at all. Find them, make sure they are both soundly connected. undo them and re tighten them. You could disconnect the plugs at the ecu and check the relevant ground pins at the PLUG are connected to ground using a continuity tester function on your multi meter, as well as physically finding them at the engine and checking them mechanically and visually. I am away tomorrow, but later I can take a photo of a set of runners off an engine and indicate where they should bolt to on a 2JZ. I suspect a 1JZ will be the same though. I can help with that bit. The black wires in centre of pic are ECU grounds. http://www.mkivsupra.net/vbb/attachment.php?attachmentid=187142&d=1402933309 These are the very earths David and I found had been left off on my wife's NA, it had been with a couple of people and had not run properly for years. I suspect the only time it had been running was when the tags had been rubbing against the block/runners. The fault finding trail started to make real progress when I discovered we had nearly 8 volts coming out of the TPS/MAP sensor feed from the ECU instead of 5v and 2 volts on the earth pin of the MAP sensor in respect of the -ve side of the battery. I did mention to check this voltage in post 27 as that shows up the missing earth immediately. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 16, 2014 Share Posted June 16, 2014 As an aside, MR2's have a similar ECU grounding set up and it's common on those for them to be forgotten when an engine is removed and refitted, or the head pulled. I think one is a main 12V ground and the other the 5V reference ground. Thanks for the photo, saved me a job Quote Link to comment Share on other sites More sharing options...
mclarenross Posted June 16, 2014 Author Share Posted June 16, 2014 These are the very earths David and I found had been left off on my wife's NA, it had been with a couple of people and had not run properly for years. I suspect the only time it had been running was when the tags had been rubbing against the block/runners. The fault finding trail started to make real progress when I discovered we had nearly 8 volts coming out of the TPS/MAP sensor feed from the ECU instead of 5v and 2 volts on the earth pin of the MAP sensor in respect of the -ve side of the battery. I did mention to check this voltage in post 27 as that shows up the missing earth immediately. Hi guys, firstly I really appreciate the input! I found tonight that my map sensor was plugged in on the wrong side of the intake plenum, that might explain the running rough. I'm going to go over all the earths with Rory later this week. We checked the map sensor voltage the other day and it was 5v ( sorry forgot to post that ) and we'll check the earths at the ecu, ( although I think they should be ok, as the high imp setting is triggering the earths) ive definitely got the two earth straps under the intake bolted to the plenum, but will unbolt and do them up again. haha Shane, I wish you did live a little closer :-) thank god for this forum though or else I wouldn't know where to go! Quote Link to comment Share on other sites More sharing options...
mclarenross Posted June 16, 2014 Author Share Posted June 16, 2014 (edited) Ok, so I pulled the plugs, removed the two earths gave them a good clean all round.... crank it... and finally she fired into life... Relief! However she is now reving up and down up and down, would this be the ecu trying to relearn or a boost leak or some thing not plumbed in right ....? Could it be my throttle position sensor? ( as I'm not entirely sure if that went back together properly...) Edited June 16, 2014 by mclarenross (see edit history) Quote Link to comment Share on other sites More sharing options...
Shane Posted June 16, 2014 Share Posted June 16, 2014 Ok, so I pulled the plugs, removed the two earths gave them a good clean all round.... crank it... and finally she fired into life... Relief! However she is now reving up and down up and down, would this be the ecu trying to relearn or a boost leak or some thing not plumbed in right ....? Could it be my throttle position sensor? ( as I'm not entirely sure if that went back together properly...) Well done. I assume thats with the resistor pack connected? First thing that springs to mind is that your ecu is mapped for 440 injectors and you are running 550s. That alone is going to give it a headache and it will be running really rich. Where is the vacuum pipe for the map sensor run from now? How are you going to adjust your fueling? The tps setting is pretty important so you should check this too if you have had it to pieces. But glad you are getting there. Quote Link to comment Share on other sites More sharing options...
mclarenross Posted June 16, 2014 Author Share Posted June 16, 2014 The map runs to the filter on the intake side nearest the cams, just above the front cam shaft sensor( pretty certain it goes there). I've got a safc2 controller that I've turned all the settings down by 22%. I'm going to have another look tomorrow at the tps Quote Link to comment Share on other sites More sharing options...
Shane Posted June 17, 2014 Share Posted June 17, 2014 The map runs to the filter on the intake side nearest the cams, just above the front cam shaft sensor( pretty certain it goes there). I've got a safc2 controller that I've turned all the settings down by 22%. I'm going to have another look tomorrow at the tps OK that sounds good, I was going to point you in the direction of a safc2 I have for sale at the moment, but you have that side sorted well it seems. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 17, 2014 Share Posted June 17, 2014 The TPS needs setting PRECISELY as stated in the shop manual. The up and down oscillating idle may also be an air leak on the plenum side of the throttle plate. But of course it could also be the ecu trying to make sense of the bigger injectors. I am not sure why you have those, are there other mods? SAFC? Quote Link to comment Share on other sites More sharing options...
mclarenross Posted June 22, 2014 Author Share Posted June 22, 2014 (edited) So I'm still not getting much further, we've been working on her this morning, and she is still revving up and down, from about a 1000 to 2500 ( Chris, yeah, single turbo 264 cams and safc2) checked tps and calibrated and still up and down, she runs rich (smells rich) and on my afm it's around 13. ( she's sounds great when we rev her over 2500 revs)I have my safc2 dialled down about 20% could this be affecting the revs, worked fine before on the 440cc injectors. Checked, double and triple checked that there is no leaks on the intake side. Tried self diagnosing with obd2, but not getting any lights flashing on... Could it be ecu ? Any ideas with these symptoms? ive also got a FCd wired in, could that be creating the issue? Edited June 22, 2014 by mclarenross (see edit history) Quote Link to comment Share on other sites More sharing options...
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