mellonman Posted June 3, 2013 Share Posted June 3, 2013 rick did you ever get to the bottom of this , im struggling with a misfire my self , its just a cold start one start the car fine for about 1minute them will miss loads sometimes and another 2-3 minutes after that it will be fine i have changed plugs (but i may do again just in case) coil packs coil clips bypassed fuel pump ecu new injectors i have a AEM fic and starting to think it could be that, anyway just wondering on what you found if it could help me Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted June 3, 2013 Author Share Posted June 3, 2013 TBH mate unless there is a further post relating to it, I'm dammed if i can remember what the cause was, it was five years ago LOL! all i can say is that i must have cured it though. Trouble is i was probably running hybrids in TTC mode at that point don't think i had gone single just then, it may have been down to injector lag times, i can remember having problems getting these to an acceptable setting, and they do cause a slight pop and irregularl idle, so it worth having a play with the settings. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 3, 2013 Share Posted June 3, 2013 What's an AIM FIC? Will it log sesnor outputs? Sounds like a temp sensor is giving a none logarithmic output, or the map has a glitch in it related to coolant temp? Quote Link to comment Share on other sites More sharing options...
mellonman Posted June 3, 2013 Share Posted June 3, 2013 (edited) What's an AIM FIC? Will it log sesnor outputs? Sounds like a temp sensor is giving a none logarithmic output, or the map has a glitch in it related to coolant temp? the AEM fic is a simple piggy back ecu , so alot of the stuff the stock ecu does , it was working perfict once apon a time but has gotten worse and worse, as you know i have replaced the injectors im thinking of changing my plugs back to a hotter grade just incase its that ? i have the ngk BKR8EIX Edited June 3, 2013 by mellonman (see edit history) Quote Link to comment Share on other sites More sharing options...
mellonman Posted June 3, 2013 Share Posted June 3, 2013 What's an AIM FIC? Will it log sesnor outputs? Sounds like a temp sensor is giving a none logarithmic output, or the map has a glitch in it related to coolant temp? sorry just to add i have also changed the ecu water temp sensor but still the same, just comes off fast idle quicker Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 3, 2013 Share Posted June 3, 2013 Changing stuff ad lib is not the way to do it. People think there's something magic about Supras. To *ANY* properly trained *DIAGNOSTIC* mechanic, or just experienced auto electrician, an engine is an engine. It needs fuel and air in the right mix, igniting at the right time. It's that simple. Once a few basic tests show the engine is probably mechanically sound you need to look at ignition firing signals, injector control signals, and coil output waveforms. That aside, I would suspect any ECU "kludger" first, or its wiring. Have you got a wide band Lambda sensor on it, that will log the readings, or atl let you watch them in real time? No decent garages near you that have a good diagnostics guy? Quote Link to comment Share on other sites More sharing options...
mellonman Posted June 3, 2013 Share Posted June 3, 2013 yep have a wide band and could log it with the AEM software i will get the data log software and have ago. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 3, 2013 Share Posted June 3, 2013 Post up a trace of the mixture before, during and after the misfire. Quote Link to comment Share on other sites More sharing options...
mellonman Posted June 3, 2013 Share Posted June 3, 2013 After your prep talk its just a engine it doesnt need much to run, I went at it going over all ecu connection and started to check injector feeds, pulled number one injector while I had misfire and no change , so checked wires from injector to ecu and they was ok , so went to check the condition of the plugs, and coil packs unplugged and plugged in the coil clip , and was not missing again , so proceeded to check the clip conections inside and took it apart bent the legs up, put back together and still the miss so moved the wires and stopped missing, so thought the wires where broken to the coil pack, so stripped the wire back as far as I could to replace and look what I found inside the heat sheald, Well the good news is that its not missing anymore but we will see as it was getting hot while I was testing it running but in sure it might be done, im shocked how far back the wires where damaged Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 3, 2013 Share Posted June 3, 2013 Cut those and repair with proper adhesive lined crimps that you heat when crimped. Looks like you fond the problem! Well done! Quote Link to comment Share on other sites More sharing options...
mellonman Posted June 3, 2013 Share Posted June 3, 2013 Cut those and repair with proper adhesive lined crimps that you heat when crimped. Looks like you fond the problem! Well done! Done and done At least I have spare injectors now lol. Brandshatch here I come Quote Link to comment Share on other sites More sharing options...
bigbloodyturbo Posted June 3, 2013 Share Posted June 3, 2013 Funny I'm chasing a missfire under load at 4krpm and during my google searches I've found your exact same problem mentioned in atleast three different threads on supraforums, guys saying they traced missfires back to coilpack wiring shorting out from dodgy insulation. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 3, 2013 Share Posted June 3, 2013 Done and done At least I have spare injectors now lol. Brandshatch here I come I would be wary of re-using those first injectors! If you decide to sell or re-use and you cover the postage, I'll check them quickly again, to see if storage has made them sticky again, FOC. Quote Link to comment Share on other sites More sharing options...
mellonman Posted June 4, 2013 Share Posted June 4, 2013 Funny I'm chasing a missfire under load at 4krpm and during my google searches I've found your exact same problem mentioned in atleast three different threads on supraforums, guys saying they traced missfires back to coilpack wiring shorting out from dodgy insulation. wow i didnt actually thing of even looking on supra forums , looks like they may of got the jump on us there but it is much hotter out there so may happen more . Quote Link to comment Share on other sites More sharing options...
mellonman Posted June 4, 2013 Share Posted June 4, 2013 I would be wary of re-using those first injectors! If you decide to sell or re-use and you cover the postage, I'll check them quickly again, to see if storage has made them sticky again, FOC. Thanks for the kind offer chris true gent, Quote Link to comment Share on other sites More sharing options...
bigbloodyturbo Posted June 5, 2013 Share Posted June 5, 2013 wow i didnt actually thing of even looking on supra forums , looks like they may of got the jump on us there but it is much hotter out there so may happen more . you probably wont believe this but I just checked my coilpack harness and I have EXACTLY the same damage in EXACTLY the same place on cylinder one coilpack clip wiring. I'll take a picture but it's literally identical:blink: Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 5, 2013 Share Posted June 5, 2013 It's not that uncommon, people use cutter crimp connectors to do diagnostics off No 1 cylinder coil pack, if they don't have current clamps or a means of back probing the connector. Quote Link to comment Share on other sites More sharing options...
bigbloodyturbo Posted June 6, 2013 Share Posted June 6, 2013 It's not that uncommon, people use cutter crimp connectors to do diagnostics off No 1 cylinder coil pack, if they don't have current clamps or a means of back probing the connector. I'll admit I do have a habit of using the old croc clip and needle technique to probe outputs from various things. Around where the break in the insulation is it looks like its seen a lot of heat, insulation has gone brittle and many of the strands in the core have broken. I've got some double insulated teflon coated high temperature wire we use downhole, i'll repair it with that, be able to hold a blow torch on it then:) Quote Link to comment Share on other sites More sharing options...
mellonman Posted June 6, 2013 Share Posted June 6, 2013 I'll admit I do have a habit of using the old croc clip and needle technique to probe outputs from various things. Around where the break in the insulation is it looks like its seen a lot of heat, insulation has gone brittle and many of the strands in the core have broken. I've got some double insulated teflon coated high temperature wire we use downhole, i'll repair it with that, be able to hold a blow torch on it then:) yep exactly what i had few strands damaged , but you wont belive it after that yesturday i went out and checked all the wiring and it was not the only one to be damaged !!!! i had damage on 1,2,and 4 in the end i completly cut out damaged wires and re run new . Quote Link to comment Share on other sites More sharing options...
mellonman Posted June 9, 2013 Share Posted June 9, 2013 Post up a trace of the mixture before, during and after the misfire. Right I still have this miss its starting to get to me now, I have just down loaded all the log software what is going to be the most useful snsors to log you said mixture but I can have a plot of alot of inputs Engine speed Engine load Boost Afr Injectors 1-6 Timing Fuel trim Battery Quote Link to comment Share on other sites More sharing options...
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