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cj

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Everything posted by cj

  1. http://jdmfsm.info/Auto/Japan/Subaru/Impreza/
  2. cj

    Poor idle

    The VVT is turning on and off repeatedly in your logs in line with the idle fluctuations so is probably at least part of the problems. I hadnt noticed your short pulse width adder table is all zero's though which is what adamw is talking about. On injectors that big Its probably contributing a fair bit to the problem as well. In fact the short pulse width adder table from ID has values up past the 0.6-0.8ms your seeing at idle, so not having that populated will be having an impact. Adding these in will only affect the idle and very light throttle parts of your tune so is a safe change to make.
  3. cj

    Poor idle

    I did some more digging on this engine and its VVT and Brad is right, it looks very on/off. Looks like mechanically the timing belt only drives the intake cam, and an actuator on the timing chain tensioner for the chain between the intake and exhaust cams allows it to push the chain to take a longer path and therefore phase one of the cams by about 15 degrees relative to the other one. It appears to only have up or down positions though and not able to move to any intermediate positions. http://forums.vwvortex.com/showthread.php?569755 see post #23 on this forum for a good explanation. There
  4. cj

    Poor idle

    Seems like no-one so far is overly familiar with this motor so we cant advise you very well on when to use the VVT functions on this motor. Do you have a service manual or some sort of general description on when the factory ECU enables this and what its trying to achieve, or what it actually does to the cams/valves/etc? Even in the part of your log when your idle fluctuations only go between 800 and 1150 or so (and are below the cam switch RPM) the same fluctuations are visible, so changing the cam switch point up to 1500 will help rule it out, but I dont expect you will see much improvement
  5. cj

    Poor idle

    As Iceman_n says, your VVT config looks a little odd considering the first couple google results suggest these engines have variable cams and not on/off. That being said, your idle fluctuations are not (entirely) caused by this. Only around 1 in 5 idle "cycles" is getting to a high enough RPM to have the cam switching kick in. The majority of your idle issues look to be related to how idle ignition timing is set up. Because your throttle opening at idle is set quite high at around 6%, the idle timing is set quite aggressively to attempt to pull your idle down to the 1100 its being asked for -
  6. You can build a frequency divider using a chip like this https://www.jaycar.com.au/4024-7-stage-ripple-carry-counter-divider-cmos-ic/p/ZC4024 which are available for a couple $ at most electronics shop. Depending on how you wire them they can divide square wave frequency by between 2 and 1024. Max input frequency is between 5 and 15Mhz depending on input voltage so should handle your turbo fine. You just need one of these, a pinboard to solder it to, a small (ideally waterproof) box to mount it in, a couple pullup resistors depending on your source sensor output, and a socket of some sort you
  7. Thats really interesting that the factory beams tacho's are that high a resistance. The 43K on the ignitor driven tacho sounds like the same number I found, but the guys providing the details of this mod long before I did mine all talk about <10K resistors being put in place on the 43k one. I cant remember exactly what resistance I used but it was less than 20, and anecdotally quite a few other people have had it work with smaller numbers too. I'd guess we should have all used 23k resistors to match toyota spec, but its a lot of effort to swap it when its already working. Hopefully the next
  8. You dont need to add any pullups or any other new resistors. Just take out this one and replace it with a smaller one (around 1k-5k). Note that your tacho layout may be slightly different, follow the traces from the IG- input pin, its pretty obviously the first big resistor the trace hits.
  9. Yep I think you got lucky. Coil packs means the ECU was already driving the tacho directly, just like a link or other aftermarkert ecu will do. The older Toyotas that had distributors had the tacho driven from the ignitor, and while I seem to recall its still from the IG- pin on the ignitor, its pushes way more voltage than an ECU would (either 40 or 80v from memory), so the tacho is set up to drop that voltage to something safe for its internal circuitry. We are talking about replacing the resistors that perform that voltage drop with something that drops it a whole lot less because now our s
  10. No pullups or new resistors needed. You just replace a couple that are already on there with smaller ones. From memory I used a 5k ohm in place of the 43kohm one you take out. A couple of those internet threads talk about repalcing the resistor with just a wire but that feels like a bad idea. I used either a 1/4 or 1/2 watt resistor from jayar. About $2 for a pack of 5 or something. [edit] Just to be clear, you need to remove a resistor from the back of the tacho and replace it with a smaller one. Comments about "a resistor on the signal wire" actually refer to the traces on the back of the
  11. Theres a realatively well known tacho mod you can do to 90's toyota tach's to change them from needing a coil level signal to just needing a "normal" signal from any aftermarket ECU. http://www.6gc.net/forums/index.php?showtopic=89365 Read down the page about halfway. I've done it myself on an MR2 and it works perfectly. Basically these toyota tach's are internally capable of accepting a normal 12v or ground pulse that every aftermarket ecu sends out, but they put a couple massive resistors in there to dampen the signal that comes off the ignnitor down to the right level. Obviously if you fee
  12. Well your trigger scope still looks the same but you now have sensible looking RPM numbers being displayed between 24 and 32 seconds into that log where it looks like you're cranking it over.
  13. 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 th
  14. 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 u
  15. 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 ha
  16. 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 s
  17. 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 it
  18. 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).
  19. 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.
  20. 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 f
  21. 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
  22. 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
  23. 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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