puddles Posted July 20, 2015 Share Posted July 20, 2015 Cool, the stock sequential system is awesome and really responsive. There are a bunch of solenoids you can still remove to make life easier. Taking out the emissions gear makes a lot of space. Use 330 ohm resistors to fake any solenoids you remove. 1 Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 20, 2015 Author Share Posted July 20, 2015 Are you able to put up a screenshot of the scope on the injector pulse. Yes, I did save one, I'll pop it up later on. Hopefully if I get back from uni early enough today I'll have time to scope out all the others. I'm actually only a part time student, but I'm responsible for the electrical systems on this year's FSAE car, so that take up ALOT of time. But uni has a dyno, and I get to play with it, so it's totally worth it . Cheers heaps for the info Puddles, that's really helpful. Getting rid of any emissions gear is on the todo list for sure. 2 Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 21, 2015 Author Share Posted July 21, 2015 Scopes of the injector signals, ordered Front Primary, Rear Primary, Front Secondary, Rear Secondary. They all look pretty much as I would expect. No action on the secondaries, which makes sense. FP: RP: FS: RS: Took the MAP sensor off to test, will jump on that when I get a spare chance tomorrow. Quote Link to comment Share on other sites More sharing options...
Popular Post yoeddynz Posted July 21, 2015 Popular Post Share Posted July 21, 2015 Make sure the carb has been topped up with damper oil. Plus the points may have closed up a little since it's fresh from a rebuild. Although I'm sure you know this because you appear the knowledgeable type. I just like to help. 18 Quote Link to comment Share on other sites More sharing options...
f100_dreamin Posted July 21, 2015 Share Posted July 21, 2015 Have you got fuel pressure at the time of scoping the injectors? I ask as after the induced spike the voltage drops really fast Usually I would expect to see a more gradual drop with a pintle hump (as the injector pintle drops to the seat, the metal pintle moving out of the injector windings creates a small current) Quote Link to comment Share on other sites More sharing options...
Dell'orto Posted July 22, 2015 Share Posted July 22, 2015 I had the injectors tested, they were in perfect shape Quote Link to comment Share on other sites More sharing options...
f100_dreamin Posted July 22, 2015 Share Posted July 22, 2015 yeah that reading just doesn't look quite correct though, Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 22, 2015 Author Share Posted July 22, 2015 I'll scope them again tonight with a better time scale, get some more detail. Great info, cheers. I've ordered a fuel pressure sensor, but its coming from China, so might be a couple of weeks. Quote Link to comment Share on other sites More sharing options...
sr1600 Posted July 22, 2015 Share Posted July 22, 2015 Can the injector sizes be swapped in these? ie primary in the secondary location? 1 Quote Link to comment Share on other sites More sharing options...
Dell'orto Posted July 22, 2015 Share Posted July 22, 2015 Not easily no. Definitely correct orientation, and flow rate Quote Link to comment Share on other sites More sharing options...
tortron Posted July 22, 2015 Share Posted July 22, 2015 man i love root cause analysis, you have acess to some neat stuff too. Good luck with it maybe overcomplicated for something with alot of wires but i have in the past printed out a large scale diagram of the wiring system (or any other system) to keep on the wall, then record any data direct on it to help remember. Green highlite the bits that work Quote Link to comment Share on other sites More sharing options...
downtrail Posted July 22, 2015 Share Posted July 22, 2015 Whats actually wrong with it? Quote Link to comment Share on other sites More sharing options...
flyingbrick Posted July 22, 2015 Share Posted July 22, 2015 The rotary is getting poor economy 5 Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 22, 2015 Author Share Posted July 22, 2015 Hah, that's a problem that'll never be fixed. Main symptom is that is seems to massively overfuel. Wont idle correctly, and fouls sparkplugs very very quickly. I just plan to keep ticking things off the list till it gets figured out. It's a fun game, and I'll learn heaps about a model of car I've never played with before. Quote Link to comment Share on other sites More sharing options...
kyteler Posted July 22, 2015 Share Posted July 22, 2015 Doesn't that point to AFM/MAF, Idle mixture control or Choke/Cold Start Enrichment? (as well as injectors but you seem to be ruling them out already.) Although far more clever in the RX-7, the 30 running rich was a shitty/incorrect AFM. I swapped between 3-4 that were from a mixture of cars but all supposed to suit the same engine (except one but I wanted to rule that out) before finding one that worked and even then it would sometimes not which ended up being a poor connection of the plug to it. I don't know what the FD runs in that regard but that's where I would be looking. Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 22, 2015 Author Share Posted July 22, 2015 No AFM's in these cars, they run a speed density (MAP and IAT sensor) configuration. Didn't get a chance to test the MAP sensor yesterday, but I have it with me in the uni workshop today, so will see how it compares to the factory specs. I really need to get another probe for my scope, so I can overlay spark events and see how they align with the injector pulses. Looking at it again, those pulses are 50ms in length, and that seems really long for what are supposed to be 550cc (thats 27.5cc's of fuel!) injectors... If it's one injection pulse per ignition event (which I would assume... but you know what they say about assumptions). Looking at those scope pics, there are around 275ms between each injection event start, meaning ~3.6 events per second, or ~218 per minute. There is one combustion event per rotor for each revolution of the eccentric shaft, so this would correspond to the motor rotation at 218rpm during cranking. This sounds about right, leading me to believe it is one injection event per combustion event (sequential). Need my bits from china to show up so I can continue the fun! . 1 Quote Link to comment Share on other sites More sharing options...
downtrail Posted July 22, 2015 Share Posted July 22, 2015 I see you have a tps fault. They normally signal when a motor should be idling with most factory computers. Id set that up first. Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 22, 2015 Author Share Posted July 22, 2015 Good plan, it's now on the list for tonight Quote Link to comment Share on other sites More sharing options...
mjrstar Posted July 22, 2015 Share Posted July 22, 2015 is that 50ms just for initial crank enrichment or when it's actually idling. Sounds like 10x too much at idle Quote Link to comment Share on other sites More sharing options...
ProZac Posted July 22, 2015 Author Share Posted July 22, 2015 Even accounting for crank, cold start, and other enrichments, that seems like a lot! However, I am ignorant of most things rotary . Quote Link to comment Share on other sites More sharing options...
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