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cj

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Everything posted by cj

  1. Looks like the flywheel at least uses the same trigger pattern as stock, its 3x groups of 10 teeth, with a gap of 2 teeth between each (so 36-2-2-2). That means the second and fifth groupings of crank teeth in that scope are from the same teeth, and the exact same issues with the waveform are present. It may not be sensor noise and may be some scratches/bad machining/other mechanical problem with those teeth on the flywheel. can you pull the crank sensor out, shine a torch down the hole, and get a helper to slowly turn the crank by hand with a breaker bar? See if you can spot any issue with the first and last teeth on 1 of the groups of 10. Also, try removing the spark plugs and getting another scope capture just in case those weird patterns are something to do with engine speed slowing down on compression strokes or something like that given you say the battery is low.
  2. Do you have a VQ35DE or a VQ35HR / VHR? As per this thread here http://forums.linkecu.com/index.php?/topic/6374-g4-thunder-dual-dbw-nissan-vq37hr/ the hr engines and the VQ37's run a different cam trigger than the DE's and the signals are inverted Also, this image here, which is the first google result for VQ35 crank trigger, shows a 5 tooth cam trigger (same as the thread above, but different phasing), whereas your scope looks like it only shows 3 teeth on the cam trigger (and just the cam signal is inverted). Are you sure you're running the stock cams, trigger wheels, pickups, etc? Are you using the intake or exhaust cam for the trigger 2 signal?
  3. That lean condition starts right when your acceleration enrichment stops and the effective injjector pulse width does actually drop a little so it looks like you simply dont have high enough fuel table numbers at that point, or you need your acceleration fuel enrichment to last longer. Your fuel table kind of shows a higher value at 2500-3000rpm which you maybe just need to expand up a few hundred RPM but as Brad says, the whole fuel table is very spiky in general. You've also got half a dozen knock detections at about the 9 second mark in that log (around 6000 rpm) which your knock control has dealt with, but they look "real" in that with a few degrees of timing pulled the knock stops, then as soon as the knock timer expires half a second later and the timing gets put back, there is another knock detection. I'm guessing the 80% ethrottle target until 4500 rpm is intentional and maybe for basic traction control? You've also got a 2% minimum ethrottle target at all RPM's which may mean your engine breaking is quite light and revs may even hold a little between gears as your throttle never fully closes. If you drop this to 0% target above say 2500 or 3000rpm you'll still be able to idle but the throttle plate will close completely on decel.
  4. There are only 1 or 2x 5v reference outputs on the link though, which means you more than likely split it into 5 or 6 wires to feed all the 5v sensors. Anywhere you ran a wire that takes 5v can potentially short onto a 12v wire, and once that 12v gets onto the wire, it "flows" out to every sensor fed by the same "5v" wire. Have a look at anywhere you've wired in a 5v sensor for a start. I'd guess that somewhere you've connected a 5v ref line to an existing wire that feeds a sensor, but that wire was already getting 12v fed to it by another source. Could also be that you've run a 5v wire to a sensor thinking you're powering it, when its acutally powered by 12 on another pin already, and so power is now running through the sensor from 12v to 5v. If that fails, unplug every single connector on the engine but leave the ECU connected, power up and check for 5v on that MAP pin again, this tells you if its a badly wired sensor of a loom issue. If its still 8.4V, unplug the ECU connector, and any link>chassis connectors so you have the engine harness completely unplugged. Then test for continuity between the 5v ref pin/pins on the link connector, and every wire in every plug on the engine harness. you should only find continuity to 1 pin on each of the 5v sensors, and if you find continuity to *anything* else, that wire is somehow bridging onto the 5v pin. If you put together a list of which wires 5v is "leaking" onto, hopefully it can be used to track down where in your loom you have a short between a 5v wire and probably a 12v wire, and worst case, you pull your loom apart and physically follow the problem wires looking for connections to incorrect things.
  5. cj

    Idle up and down!!!

    I notice your fuel table slopes the wrong way in the regions where its doing the cyclic thing. @ high revs the fuel table drops, and at low revs the numbers are highers. Kind of looks like its cycling because it wants to idle at the high er revs based on throttle & spark, but doesnt have enough fuel so it leans right out then the revs start to drop, once its back in a roughly right a/f mixture the revs try to climb again to match your throttle opening. Try adding 3 or 4 points to the fuel table around where it "peaks" at while doing the cyclic thing or smooth it out a bit manually so its a pretty consistent slope upwards as the revs/load increases
  6. MGP should roughly match your gauge. (MGP = Manifold Gauge Pressure). -21" is -10.3 psi so while its not dead on, its in the same ballpark. Also, -7.4psi MGP sounds like a reasonable number for idle vacuum. When the engine is off, but ECU on, does it read roughly 14.7psi/101kpa? If this checks out, i'd say your MAP sensor is reasonably healthy. Do any other sensor values jump out at you as wrong? hit f12 and have a look at the various runtime value and if anything looks completely out of line with reality (eg when its cold with ECU on and engine off, most temps will be within 5deg of ambient). When its running badly with everything plugged in, is your AFR high or low? can you post a log and your pclr please?
  7. According to the last recorded value in the log you posted, your IAT's are about 60deg C. At this temperature, your IAT correction is pulling between 0.5 and 8% of fuel so disabling this should get your VE quite a bit more accurate. Heres a pretty generic sample image of a VE table. No idea what engine this is from (first result from google), but it shows you the general shape that most engines will want. It looks like the left column is MGP.
  8. Heres a starting point. I've done the same swap into an SW20 over the last year or so with a Fury ecu The spreadsheet tables "LinkECU" and "Tune" are probably the most interesting to you. The pinouts tab will only be relevant to a k20z4 as the earlier K20A engines ran different plugs to the ECU. You'll have to sanity check a few things yourself and probbaly change a few other to match your engine and chassis, but its a starting point. The tune is not complete, its my weekend tinkering project so it runs well enough to go around the block pretty well but not fully tuned by any stretch. Except for the fuel table, most of it is translated from the hondata base maps. the spreadsheet and pclr injector details dont match up either as its now running evo X injectors. ecu-body wiring factory.pdf pinouts.xlsx k20z4-24.3-550cc-ve.pclr
  9. That base map was originally running traditional fuel map right? The numbers in the fuel table are way too low for a modelled VE table. as a starting point, multiply everything in the table by 1.7 so that the number at ~3500 @ 100kpa is around 100. This lines up with most of your symptoms too : changing injector size to 400 means the ECU basically doubles the fuel amount. I assume you mean changing the refernce pressure in the ECU rather than acutally changing your pressure reg? In that case, same thing, ECU thinks you've got half the pressue so double the pulse time (ie double the fuel) The numbers arent quite double because of a dead time etc but you get my point. Also, the manual says to disable IAT calibration to start with when using modelled fuel
  10. I notice from your first PCLR and log file that you've really only tuned below about 2000rpm, but your test run spends most of its time about 2000rpm where you have compltely untuned 70 values in most cells. Assuming your lambda sensor is set up correctly, then its running very lean (1.2 lambda) for 90% of your log, which explains it running badly. There are a few seconds in your log about 1:26 where you're speeding up in a tuned section of the fuel map, and while its not at your target lambda (0.85), you are at least getting a reasonable lambda number (0.95ish). Try putting sensible guesses into the untuned part of the map, or simply using the mixture map function with a log file to roughly adjust the untuned numbers. If it still runs terribly with a roughly correct fuel map then go looking for other problems. Have you had a look at the fuel maps in a couple of the modelled fuel base maps? They tend to look roughly flat at 90-110 for the majority of the map above 60-80kpa, drop off to 50-60 below 1500rpm or so, and slope down to 50-60 between 80kpa and 20kpa. There are a few bumps around peak torque, but they dont slope smoothly from 20 up to 100ish like a traditional map does. Google up volumetric efficiency table and have a look at the shape of them for any engine/ecu - even though the numbers may be different than what link uses. I've never tuned a rotary, but if that was a piston engine, I wouldnt expect the <2000rpm fuel table to be far off what you've go so far, so dont actually see a problem with the ~80-90 values you've got in there. Remember, this isnt directly a "how much fuel do I use" number in modelled, its a "how efficient is the engine running vs its theoretical maximum at this amount of engine load" number. so another part of the equation in the background already deals with the fact that you need more fuel at 200kpa at 6000rpm than you do at 110kpa at 3000rpm, these numbers may both be say 105 on a finished fuel map.
  11. The Subaru ethrottle i've got on a bench looks like it naturally stops around 5% closed if no current is applied, but can be driven fully closed by the motor if needed. I guess its a good failsafe position?
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