Kali Posted June 2, 2011 Share Posted June 2, 2011 So basically its what stated at the topic description. While im cranking i have spark, WOO HOO, but my injectors are not firing. So i have 420cc injectors, running at 44psi. Under injectors charaterisics injector opening time under 1ms, battery voltage correction is at .1, PWM is at 100, and PWM time threshold at 25.4. Im pretty much at a stand point. Also if someone can decribe on how to export MSQ files. Im talking with Matt Cramer from diy and he needs to see my MSQ and all im getting is word files. Any help will be appreciated. THanks Quote Link to comment Share on other sites More sharing options...
Cannonball89 Posted June 2, 2011 Share Posted June 2, 2011 What is your cranking RPM? If that is set too high it might cause that. Also what is your cranking pulsewidth? If its at 0 then that could be your problem. Another thought, where is the +12V to the injectors coming from? If it is coming from any circuit on the accesory relay it will have no power during cranking. Good luck, hope you figure it out. Quote Link to comment Share on other sites More sharing options...
Kali Posted June 2, 2011 Author Share Posted June 2, 2011 (edited) crnking RPM is about 135 cranking PW is set to 6.5 last part i didnt understand Thanks I'll check over my settings just to make sure Edited June 2, 2011 by Kali Quote Link to comment Share on other sites More sharing options...
s30red240z Posted June 2, 2011 Share Posted June 2, 2011 crnking RPM is about 135 cranking PW is set to 6.5 last part i didnt understand Thanks I'll check over my settings just to make sure if the injectors have voltaje supply when you start the car. Quote Link to comment Share on other sites More sharing options...
Kali Posted June 4, 2011 Author Share Posted June 4, 2011 if the injectors have voltaje supply when you start the car. Hmmm... i guess not they do get voltage on the higher rpms just not while its cranking. Could my Pulse Widths settings be off? Quote Link to comment Share on other sites More sharing options...
Kali Posted June 4, 2011 Author Share Posted June 4, 2011 (edited) @ Cannonball89 Well i used the wiring diagram via this link http://forums.hybridz.org/index.php/topic/69077-msd-ignition-megasquirt-wiring/ So lets say it is the relay. Then what would that mean i would have to replace it? Maybe a possible short would burn the relay and not allowing the circut to seperate during cranking? Im sorry if i way off my knowledge towards this kind of thing is very limited. Edited June 4, 2011 by Kali Quote Link to comment Share on other sites More sharing options...
Cannonball89 Posted June 4, 2011 Share Posted June 4, 2011 crnking RPM is about 135cranking PW is set to 6.5last part i didnt understand Thanks I'll check over my settings just to make sure I mispoke about cranking RPM. What I should have said is that if the cranking RPM is set too low in Tunerstudio/Megatune, then MS won't fire the injectors at the cranking pulsewidth. IF your cranking RPM is 135 RPM, then your cranking RPM setting should be at least @ 200 RPM. Anything above what your cranking RPM setting is at will fire the injectors at whatever pulsewidth it derives from your table settings. Lets say your cranking RPM is set at 100 RPM... then at 135 RPM it will be trying to derive a pulsewidth from your table settings, which probably only go down to ~500RPM or so, so basically MS might calculate a 0ms Pulsewidth. See below for an explanation of the +12V to the injectors. @ Cannonball89 Well i used the wiring diagram via this link http://forums.hybridz.org/index.php/topic/69077-msd-ignition-megasquirt-wiring/ So lets say it is the relay. Then what would that mean i would have to replace it? Maybe a possible short would burn the relay and not allowing the circut to seperate during cranking? Im sorry if i way off my knowledge towards this kind of thing is very limited. I see the diagram you are using, it looks good... The thing is that in an S30 you have to wire the relays such as that they are active with the ignition switch at both the "on" and "start" positions. Basically you need to have pin 30 or 87 coming from a constant 12V source and the other going to the load (in this case the injectors), then either pin 85 or 86 hooked up to ground and the other hooked up to a switched 12V source. The only good switched 12V source I could find on my 240z was from the coil + side, this is hot at both the key "on" and "start". Almost every other circuit on a 240z is either constant 12V or is 12V when the ignition switch is at "acc" or "on" and are open circuits when the key is on "start" To clarify I made a quick diagram showing my relay wiring. I would also recommend testing your wiring by disconnecting the "S" terminal form the starter and then checking to see if you have +12V at the injectors with the key on both "on" and "start" Sorry for the childish looking diagram but microsoft paint is about the only way I have to make wiring diagrams Quote Link to comment Share on other sites More sharing options...
Kali Posted June 7, 2011 Author Share Posted June 7, 2011 No worries on the drawing. Thanx though ill let you know if i get anywhere with this. Quote Link to comment Share on other sites More sharing options...
Kali Posted June 8, 2011 Author Share Posted June 8, 2011 So ive got the pulse back but ive lost the spark again.... Ok ok deep breaths... So Q5 burnt out again ordered the transistor on friday. just been crazy with training that i have to been able to focus on my car as much as id like. But im determined to get it started by August if not sooner. I think that the first time that i fried Q5 i replaced it with the wrong transistor. As posted on this other post "keep burning out Q5" i relized that when i bought the replacement for the original i bought a NPN while i believe the MS comes with a PNP, wrong polarity from what i read. I never thought those words wouldcome out of my mouth in a somewhat knowledgable form until today. Hey you always learn something new. Back to the drawing board. I should get the part here in a day or so ill let you know if its fixed. Quote Link to comment Share on other sites More sharing options...
Kali Posted June 10, 2011 Author Share Posted June 10, 2011 Put up another fixed!!! WOO HOO ive got spark pulse again and while cranking too. I was right and the polarity was in the wrong direction with the wrong transistor. Back to the tunning. FIDDLESTICKS! So im going to post another topic. If annone out there that spark table for a bored out L28 to a 3.1L turbo it would be greatly appriceated. Thanks Quote Link to comment Share on other sites More sharing options...
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