i think decel cut off is mainly for fuel efficiency, may be wrong, but pretty sure
----- Original Message ----- From: "Mark" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, August 27, 2003 5:29 PM Subject: Re: How free should T03 impeller rotate? > Justin was right on the money - the TPS was playing up, reading 0% > when it shouldn't (I didn't print or save the last datalog otherwise I > might have noticed this earlier - but it was obvious when reading the > engine data tonight after work on the trusty Toshiba). > > I disabled decel cutoff and recalibrated the TPS and woohoo! around the > block I go and what a relief - I had contemplated $$$ check & rebuild > on the turbo such was my paranoia. Now I wonder what the implications > are of not running with decel cutoff on my motor - pretty well stock > FJ20 Turbo with 2.5" exahust. > > Previously when it self-corrected it lead me to look at the turbo - > when in fact it simply must have been repeated rotation of the TPS > which flicked back into life. So now gotta add the laptop to my > emergency tool box anytime I venture more than a few hours walk from > home ;-( > > > > On Wednesday, August 27, 2003, at 04:21 PM, Robert Charles Scealy wrote: > > > Just testing a theory, on your old log does it only go to 32 when you > > are above 1700 rpm? Does it only go to 8 when you are off the throttle? > > And when you are on the throttle at all but under 1700rpm does it go to > > 0? And are all the occurances of the code 40 happen when you are both > > off the throttle and engine revs are about 1700rpm? > > > > On Wed, 27 Aug 2003 [EMAIL PROTECTED] wrote: > > > >> Here's the quote from a Tuner on the Haltech forum, I'm still > >> awaiting a reply > >> from Haltech support. > >> > >> ============================== > >> Hi Mark, > >> The engine flags reading in the software is really quite difficult to > >> dechipher > >> unless you really know what your looking at and even then they are of > >> limited > >> use. This is really a Haltech in-house debug tool .. wont really help > >> you. > >> > >> It sound like you have the decel cutoff feature catching you out. > >> > >> Step 1. Make sure your TPS is connected and correctly calibrated... > >> Best to recalibrate it to be sure ... very easy ... go to Menu and > >> select > >> calibrate throttle and do what it tells you to do. > >> > >> Step 2. > >> Go to the Fuel setup page and see if "decel cutoff" in enabled or > >> disabled. > >> > >> My bet is that decel cutoff is enabled at 1700 rpm and that is what > >> is going > >> on .... Decel cutoff will cut fuel at the set RPM when ever the > >> engine is above > >> the setpoint and at zero tps. > >> > >> It will cut back in if you come back below set RPM or if throttle > >> exceeds 1% > >> > >> Best thing to is to turn it off ... do your tuning ... and then > >> re-activate it > >> if you want to use it .. some engines are better off without it > >> (ported > >> rotaries for example) > >> > >> I hope that helps > >> > >> Regards > >> Justin K > >> Tweakit Performance > >> Sydney Australia > >> ========================== > >> > >> > >> Quoting Robert Charles Scealy <[EMAIL PROTECTED]>: > >> > >>> I find it interesting that they say it is a debug flag, and that 32 > >>> + 8 > >>> = 40. It sounds to me like value 32 and value 8 are not supposed to > >>> occur together. Do you have the exact wording of what the Haltech > >>> board > >>> said about these flags? > >>> > >>> The only time I have ever spun turbos I would say I have been able to > >>> flick them hard enough to maybe a couple of revolutions. > >>> > >>> On Wed, 27 Aug 2003 [EMAIL PROTECTED] wrote: > >>> > >>>> Trying to diagnose my FJ20ET F9 ECU that cuts out at ~1700 rpm - I > >>> thought > >>>> maybe turbo was not healthy and removed the filter and intake > >>>> piping - I > >>> can > >>>> rotate the compressor impeller quite easily - I don't expect that it > >>> should > >>>> just spin almost without friction or should it? > >>>> > >>>> I ran a datalog on a laptop and the printout shows that at the > >>>> precise time > >>> of > >>>> cutout (or surging if I maintain a steady throttle at around 1,700 > >>>> rpm) > >>>> the "engine flag" value changes from 8 to 40 and inj m/sec goes to > >>>> 0.000. > >>>> > >>>> Advice from the Haltech board is the flags are an "in house debug > >>>> tool" > >>> and > >>>> hard to decipher. > >>>> > >>>> Examining an older log when engine ran fine I do see an occasional > >>>> value of > >>> 40 > >>>> with inj m/sec 0.0000, but only rarely. Mostly it reads 0, 8, or 32. > >>>> > >>>> Also suggested was to disable decel cut-off and recalibrate the TPS > >>>> both > >>> which > >>>> I'll try tonight after work. > >>>> > >>>> Mark.JT > >>>> > >>> > >>> > >>> > >> > >> > >> > > > > > > > --membersozdat------------------------------------------------------- OZDAT Mailing List Please Note:- Send (un)subscribe requests to [EMAIL PROTECTED] Send submissions to [EMAIL PROTECTED] No unauthorised redistribution of this email http://www.ozdat.com/ozdatonline/index.htm http://www.ozdat.com/ozdatonline/listindex.html http://www.mail-archive.com/[EMAIL PROTECTED]/ ---------------------------------------------------------------------
