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Issues w the REV LIMIT on the S300j

Posted: Mon Aug 14, 2006 12:22 am
by adSPEED
here is my issue.. after dataloging my track pass, me and my tuner both noticed that after i hit the rev limiter, it does not want to turn off untill my RPM's drop to 3200... if it doesnt drop below 320o my car shuts down the injectors (being that my rev limit is fuel only), and no power is transfered to the next gear.. only time my car is ok is if i dont hit the rev limiter.. this is a jdm p72 ecu, S300, professionaly installed by one of the best hondata tuners around Howard at RLZEngineering.. we will be trying a USDM p28 and see if thats the issue, but up till then maybe there is something you guys know of, to turn that Rev limiter off once it hits... thanx

Posted: Mon Aug 14, 2006 8:35 am
by Hondata
http://www.hondata.net/forum/viewtopic.php?t=3772

Please post your calibration at least - it is the only way to diagnose some problems.

Posted: Mon Aug 14, 2006 9:27 pm
by airshifter
cali file and 2 log files, log files are long but I was trying to see everything from the begginning to the end of the runs

in log rev2 u will see it when he hits the revlimiter during the burnout, as he goes down the the track he made sure not to hit the limiter

in log revproblem u will see it happen each time the car hits the revlimiter

1 thing that I did notice was that the PSP was on and this car doesn't have that

Posted: Mon Aug 14, 2006 9:32 pm
by airshifter
EG civic hatch
built GSR
full race turbo kit
MSD billet dizzy setup but no other ignition amplifiers

Posted: Tue Aug 15, 2006 10:41 am
by Hondata
Thanks for the datalog, I can see the problem now and are working on a solution. The car looks like an absolute beast.

Posted: Tue Aug 15, 2006 11:24 am
by Hondata
The problem is from excessive noise in the pulses from the distributor to the ECU. It is also related to the smoothness of the rpm rise, which is why I think it occurs immediately after hitting the rev limiter.

Recommendations:
- Use an alternator / higher voltage battery. We've seen many problems when the battery voltage falls below 13V
- Check that the distibutor wiring is in good condition, with no taped joints, and make sure the distibutor wiring does not run parallel with any wires which may induce noise. Make sure the original shielded wiring is used, and that the shield is only grounded at one end.
- Pull the distributor and suspension tower connectors apart and clean the pins with an electrical contact cleaner.
- Try a different distributor.

Good luck.

Posted: Tue Aug 15, 2006 8:43 pm
by airshifter
here is a log from my car when the alternator belt was off and the voltage was dropping to 11.17 and we had no problem, our belt use to come off every pass and my car never acted up in any way, what are u looking at on the log to see the noise on the distributor so maybe I can see what to look for to compare his to mine and for future problem solving, we are running basically the same setup just a different turbo and he is s300j and I'm standard s300

Posted: Tue Aug 15, 2006 9:22 pm
by adSPEED
also as as airshifter did not mention my batery is relocated to the back, and current voltage at idle is 13.8 14.0... don't think an optima red top ould drop voltage, and i am runing excess amounts of grounds... the pull is very clean during the dyno session, but as i hit the rev limiter, it does not want to come off.. and now my tach stopped orking on the way home tonight.. is there anything else you would want me to do as far as dataloging?? i heavily doubt that this has anything to do with voltage, but the MSD billet dizzy might be

Posted: Sat Aug 19, 2006 10:31 pm
by locash
Interesting post, any updates on this one?

Posted: Sun Aug 20, 2006 7:28 am
by Hondata
This is the most likely cause:
The problem is from excessive noise in the pulses from the distributor to the ECU

Posted: Sun Aug 20, 2006 5:52 pm
by airshifter
put a standard s300 in the car and the problem went away

what part of the log do u look at to see this noise

Posted: Sun Aug 20, 2006 7:55 pm
by Hondata
Every ECU will have a difference tolerance to distributor noise, and I supect that you've masked the problem rather than solved it. If the car runs, fine, be keep it in mind if you get the same problem in the future.