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Thread: IQ3 questions

  1. #21

    Default Re: IQ3 questions

    Hi Mike, I have most of those.

    0 = 0, 1 = 1, not running i get 0 or near to it, idling I get around -550

    0 = 0, 1 = 0.1 I get 0 with it not running and 55 or so idling, which closely matches the vacuum in kpa reported in the ECU programming software.

    0 = 0, 1 = 0.015 (Or any near equivalent) I don't recall the non running figure but at idle it returns about +260! I will have to confirm those tomorrow.

    the next thing I was going to try was your suggested 0 = 0, 1000 = 14.5. I am pretty sure the Haltech reports negative numbers for vacuum given 0 = 0, 1 = 0.1 returns 0 not running and negative figures in vacuum.

    The only real reason I would like a PSI pressure readout is that on one dash page I want to have fuel and manifold pressures reported one above the other so a quick mental check even while on track can confirm that the fuel rail is above the manifold by an appropriate figure and it is easier to see 18PSI of boost and 55 or so PSI of fuel pressure at a glance and be happy that fuel pressure is OK rather than looking at pressures reported in hundreds of KPA and doing the mental gymnastics on that. Ideally what I wold like is a differential pressure sensor where you hook a reference port up to the manifold and a sense port up to the fuel rail and directly report in PSI or KPA the difference between the two, that being the regulated fuel pressure.

  2. #22

    Default Re: IQ3 questions

    So now with this numbers from your last post it makes things even more clear and your description from the past seems alright. Hopefully the suggested numbers will fix it.

    If it doesn't work then I would contact the user from the other thread for his numbers as he wrote that he got a PSI reading on the haltech dash. Or somebody from racepak kicks in...

    Your thoughts regarding the differential pressure sensor (manifold pressure against fuel pressure) would best fit your purpose for sure, but anyway it's interesting what's going wrong with the scaling (maybe the small number of 0.015 is hard to convert for the unit?).

    Good Luck ;-)

  3. #23

    Default Re: IQ3 questions

    OK, been there, done that, it seems to be an offset issue, with .015 plugged in I get 284 not running and 276 idling, about right for vacuum in PSI between the two. All other figures I have tried produce really wildly inaccurate displays.

    At this point it is becoming a bit of an exercise in futility. I am better off to log the fuel and manifold pressures for later checking and add an alarm for AFR leaner than 12:1 at boost above about 70KPA where a crook pump is going to rear it's head.

  4. #24

    Default Re: IQ3 questions

    Looking at AFR will work fine - as you will be able to recognize more different faults in the system with this one parameter.

    With respect to your results what about:
    0 = -284, 1 = -283,9855, min -15, max +30

  5. #25

    Default Re: IQ3 questions

    I am just sitting on it at the moment, I have other work to do on the car so I can not afford to be playing around for too long just to get the dash to display a pressure in my preferred measurement for conveniences sake. I should be able to see fuel pressure OK, at full boost I should see around 120KPA boost and around 400KPA fuel pressure. I might just live with the larger numbers and move on rather than chasing smaller numbers (PSI) for conveniences sake. I was born onlya couple of years before Australia went to metric mesurements, maybe it is time I just caught up!

    So long as I can get the USM attached sensors to display in KPA easily I think I will just do that. That should just be a matter of changing 0.5 = 0, 4.5 = 100 from the pressure transducers into 0.5 = 0, 4.5 = 690 to produce a KPA reading from the 100PSI sensors I have.

    I think unless one of the Racepak guys chimes in with something simple I have got wrong then it is time to drop the issue.

  6. #26

    Default Re: IQ3 questions

    Hi Blue,
    bumping an old thread up because I have seen some of your posts (some months ago) where you wrote about your difficulties re the kpa psi conversion in this thread.
    Did you ever tried my last suggestion? I know you were tired of trying different settings but maybe give this one a last chance?

    Quote Originally Posted by MikeD
    With respect to your results what about:
    0 = -284, 1 = -283,9855, min -15, max +30

  7. #27

    Default Re: IQ3 questions

    Actually, we had a bushfire go through our property earlier this year (February, we were lucky and did not loose anything essential but have been cleaning up and rebuilding ever since) so I have not been playing with the race car much. When I get a chance to just sit and fiddle I will give it a try, I can not recall if I already tried those figures or not.

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