Tricky-Ricky Posted August 20, 2008 Author Share Posted August 20, 2008 (edited) IMO on an ecu reset nothing changes and its all in the mind. Ryan[/quoteI i have always believed in the above statement Thanks for the info Ryan, will have a read, at a glance it looks similar to the Consult software that was available for Nissan's, so you could read the std maps, something like that for the Supra wold be good:) Edited August 20, 2008 by Tricky-Ricky (see edit history) Quote Link to comment Share on other sites More sharing options...
Hermit Posted August 20, 2008 Share Posted August 20, 2008 LOL! Noooooo! thats the whole point of the thread:p:d It makes for an interesting discussion though;) Haha, you know what I meant Besides, it's turned out to be us lot learning from Matt and Ryan's experiences, which is just dandy Thanks guys Quote Link to comment Share on other sites More sharing options...
dandan Posted August 21, 2008 Share Posted August 21, 2008 Shall we complicate things a little more and bring the Mines altered OEM ECU into the discussion. e.g. In addition to fuel cut and rev limit increase, what about the ignition timing changes from the Mines ecu? Would the OEM ecu still pull timing back and then re-introduce it like normal when the Mines daughterboard is trying to advance it more than normal? Quote Link to comment Share on other sites More sharing options...
Matt Harwood Posted August 21, 2008 Share Posted August 21, 2008 Shall we complicate things a little more and bring the Mines altered OEM ECU into the discussion. e.g. In addition to fuel cut and rev limit increase, what about the ignition timing changes from the Mines ecu? Would the OEM ecu still pull timing back and then re-introduce it like normal when the Mines daughterboard is trying to advance it more than normal? My stock ECU IS a modified one. Has caused problems with the E-manage in the past. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted August 21, 2008 Author Share Posted August 21, 2008 Shall we complicate things a little more and bring the Mines altered OEM ECU into the discussion. e.g. In addition to fuel cut and rev limit increase, what about the ignition timing changes from the Mines ecu? Would the OEM ecu still pull timing back and then re-introduce it like normal when the Mines daughterboard is trying to advance it more than normal? I would imagine yes it would, has the Mines altered ECU actually got an add on daughter board? or does it just have rewritten ROM chip, the latter i would have thought, as its more cost effective. Quote Link to comment Share on other sites More sharing options...
Guest wilbo666 Posted August 21, 2008 Share Posted August 21, 2008 http://www.autoshop101.com/autoshop15.html In particular this document... http://www.autoshop101.com/forms/h44.pdf The ECU has short term and long term fuel trims. Cheers Wilbo Quote Link to comment Share on other sites More sharing options...
SimonB Posted August 21, 2008 Share Posted August 21, 2008 I thought (could be wrong though as I can't remember where I read it) that the stock ECU stores the adjustments it last made at a particular map point while in closed loop. Kind of a long-term trim value. So if you reset it it would take a bit longer to settle down to 14.7AFR while crusing/idling/low load. EDIT:Ah, in fact Wilbo has just said the same! Quote Link to comment Share on other sites More sharing options...
Guest wilbo666 Posted August 21, 2008 Share Posted August 21, 2008 I would imagine yes it would, has the Mines altered ECU actually got an add on daughter board? or does it just have rewritten ROM chip, the latter i would have thought, as its more cost effective. With the Toyota engine ECUs (i.e. the JZA80), the microcontrollers code including the 'maps' or tuning data is stored in mask ROM (http://en.wikipedia.org/wiki/Mask_ROM) in the mircontroller. It isn't possible to change the mask ROM in the microcontroller... it is however possible to put the microcontroller into a mode so that it doesn't use its internal code (in the mask ROM), but accesses code in an external memory. So in general to make the Toyota ECU's 'programmable' you use a daughter board, with external memory that you can change / modify If the external memory is loaded with same data as the mask ROM then it would work the same as a stock ECU (it isn't quite that easy tho as some of the pins on the micro that are used for other functions are needed to read the external memory, these are then remapped to memory locations...) This is just my understanding, and might be wrong and incorrect in some regards. I think the basics of it are right tho Cheers Wilbo Quote Link to comment Share on other sites More sharing options...
Hermit Posted August 21, 2008 Share Posted August 21, 2008 I would imagine yes it would, has the Mines altered ECU actually got an add on daughter board? or does it just have rewritten ROM chip, the latter i would have thought, as its more cost effective. Inside the Tom's modified JZZ30 ECU I have here there's a daughter board with CPU and ROM chips. This replaces the original CPU which presumably had ROM built into it. So it's both but effectively a rewritten ROM chip. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted August 21, 2008 Author Share Posted August 21, 2008 Wilbo, that seems to be general ECU behaviour already mentioned, rather than Supra specific. They said that the Nissan ECU ROMs couldn't be rewritten but all it takes is for the original ROM chip to be replaced with a rewritable one, its extracting the data contained that was a stumbling block, i suspect that nobody has spent that much time on the the Supra ECU other than Mines ( and there not saying;)), because most of the big power conversions done to the Supra call for a stand alone ECU. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted August 21, 2008 Author Share Posted August 21, 2008 Inside the Tom's modified JZZ30 ECU I have here there's a daughter board with CPU and ROM chips. This replaces the original CPU which presumably had ROM built into it. So it's both but effectively a rewritten ROM chip. Ahh i stand corrected, sounds like its the same as the Nissan S15 ECUs they need an add on daughter board to interface with the original ECU and rewritten ROMs added. Quote Link to comment Share on other sites More sharing options...
ADL Mark Posted August 21, 2008 Share Posted August 21, 2008 8secSupra claims to have 'cracked' the standard ECU and seen the maps.. http://www.mkivsupra.net/vbb/showpost.php?p=996432&postcount=15 Quote Link to comment Share on other sites More sharing options...
Thorin Posted August 21, 2008 Share Posted August 21, 2008 8secSupra claims to have 'cracked' the standard ECU and seen the maps.. http://www.mkivsupra.net/vbb/showpost.php?p=996432&postcount=15 Techtom used to do a ECU reader I believe, the stock fuel map values are knocking around somewhere, I have seen them before. Quote Link to comment Share on other sites More sharing options...
Thorin Posted August 21, 2008 Share Posted August 21, 2008 http://suprasonic.org/sonictech/techtom/ Quote Link to comment Share on other sites More sharing options...
TrickTT Posted August 21, 2008 Share Posted August 21, 2008 I would imagine yes it would, has the Mines altered ECU actually got an add on daughter board? or does it just have rewritten ROM chip, the latter i would have thought, as its more cost effective. The mines ecu is quite a complicated bit of kit. They remove 2 big chips from the stock board and attach the mines daughter boards to the motherboard in place of those big chips. This is the inside of mine, its from an auto so i assume that one of those daughterboards is to run the gearbox: Quote Link to comment Share on other sites More sharing options...
Hermit Posted August 21, 2008 Share Posted August 21, 2008 The ECU has short term and long term fuel trims. Wilbo, that seems to be general ECU behaviour already mentioned, rather than Supra specific. Sure, but it's true of the Supra as well. It certainly explains why some cars take a while for their idle to settle after a reset. Mine doesn't, which I'll take as a good thing I guess the long term fuel trim is basically calibrating the ECU to the fuel delivery system of the car, but does that trim then get used for open loop operation as well as closed loop? It would at first glance seem logical if it did, but from what I've heard, open loop operation is normal after a reset (even when the idle is rough). Quote Link to comment Share on other sites More sharing options...
Matt Harwood Posted August 21, 2008 Share Posted August 21, 2008 Just out of interest, why, when in closed loop mode, would the ECU need to store any data? - With adjustments being made at 'x' times per second, surely it could sort itself out regardless. Even if you suddenly dump a load of fuel in with the emanage at idle, it'll sort itself out completely in around a second... IMHO, the only time you should need to reset the ECU is if it has been spiked and acting irregular. - With all the things I've done with mine, I've never 'needed' to reset the ECU except to clear fault codes. Quote Link to comment Share on other sites More sharing options...
SimonB Posted August 21, 2008 Share Posted August 21, 2008 Just out of interest, why, when in closed loop mode, would the ECU need to store any data? - With adjustments being made at 'x' times per second, surely it could sort itself out regardless. Even if you suddenly dump a load of fuel in with the emanage at idle, it'll sort itself out completely in around a second... With a narrowband lamda sensor only to go on all it can do is guess the fuel adjustment, then wait and do it again. If it only had a single short term trim it would overshoot and takes ages to settle. With a long term trim it can use that in combination with the short term one to settle faster. Plus I think it might use it as a basis for cold start running too when there's no lamda signal to go on. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted August 21, 2008 Author Share Posted August 21, 2008 Just out of interest, why, when in closed loop mode, would the ECU need to store any data? - With adjustments being made at 'x' times per second, surely it could sort itself out regardless. Even if you suddenly dump a load of fuel in with the emanage at idle, it'll sort itself out completely in around a second... IMHO, the only time you should need to reset the ECU is if it has been spiked and acting irregular. - With all the things I've done with mine, I've never 'needed' to reset the ECU except to clear fault codes. I am inclined to agree with that to, and exsperienced the quick re-trim of fuelling when changed by Emanage. Quote Link to comment Share on other sites More sharing options...
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