wkdtime Posted January 29, 2007 Share Posted January 29, 2007 I've heard the Yanks refer to the above in quite a few threads on Supraforums. Blonde moment here, but what is an OBD1 or 2 ECU? Quote Link to comment Share on other sites More sharing options...
Angarak Posted January 29, 2007 Share Posted January 29, 2007 I've heard the Yanks refer to the above in quite a few threads on Supraforums. Blonde moment here, but what is an OBD1 or 2 ECU? Theyre different ECU models. I think (but dont quote me) that pre-96 supra's are OBDI, and 96+ Supra's are OBDII. Quote Link to comment Share on other sites More sharing options...
JustGav Posted January 29, 2007 Share Posted January 29, 2007 OBD stands for onboard diagnoistic... It is a standard for plugging into the ecu in order to get info from it. All non vvti supra's are OBD-I... even the VVTI OBD2 is not the normal standard and requires a different unit. Quote Link to comment Share on other sites More sharing options...
JustGav Posted January 29, 2007 Share Posted January 29, 2007 On-Board Diagnostics, or OBD, in an automotive context, is a generic term referring to a vehicle's self-diagnostic and reporting capability. OBD systems give the vehicle owner or a repair technician access to state of health information for various vehicle sub-systems. http://en.wikipedia.org/wiki/On_Board_Diagnostics Quote Link to comment Share on other sites More sharing options...
imi Posted January 29, 2007 Share Posted January 29, 2007 From my Honda days, OBD1's were always easier to map and to tune - while OBD2's were harder (more variables in the map, different processor, more stocheometric closed loop mapping, and more)...... Quote Link to comment Share on other sites More sharing options...
JustGav Posted January 29, 2007 Share Posted January 29, 2007 Guys... OBD is a standard which the ECU outputs the diagnostic, it has NO effect on tuning, as it is merely a I/O specification, not the model of ECU... Quote Link to comment Share on other sites More sharing options...
imi Posted January 29, 2007 Share Posted January 29, 2007 Guys... OBD is a standard which the ECU outputs the diagnostic, it has NO effect on tuning, as it is merely a I/O specification, not the model of ECU... OBD2 has a lot to do with modding (on Honda's anyway). With stricter emissions, the OBD2 chip uses the TWO O2 sensors to closely fine tune closed loop emissions to stoch ratios. On the Honda's this resulted in the ECU DE-TUNING any changes to the AFR using a piggyback ECU for example - also basic mods like I/H/E were rendered more or less useless. In Open WOT it had no difference to an OBD1 Not exactly sure how it works on the Supra.... Quote Link to comment Share on other sites More sharing options...
JustGav Posted January 29, 2007 Share Posted January 29, 2007 OBD2 has a lot to do with modding (on Honda's anyway). With stricter emissions, the OBD2 chip uses the TWO O2 sensors to closely fine tune closed loop emissions to stoch ratios. On the Honda's this resulted in the ECU DE-TUNING any changes to the AFR using a piggyback ECU for example - also basic mods like I/H/E were rendered more or less useless. In Open WOT it had no difference to an OBD1 Not exactly sure how it works on the Supra.... Imi... OBD has nothing to do with the ECU... it is a standard as I said...The ECU manufacturer will ensure that their particular design has an OBDI or OBDII output. This is especially relevant in California. Quote Link to comment Share on other sites More sharing options...
imi Posted January 29, 2007 Share Posted January 29, 2007 Take a step back. is the OBD2 interface MORE complicated (more inputs / more outputs) than an OBD1? If so, then an ECU using an OBD2 INTERFACE will be using MORE inputs and more outputs; hence you will find OBD2 based ECUs in newer cars rather than older cars (for all the reasons that I mentioned earlier). Quote Link to comment Share on other sites More sharing options...
JustGav Posted January 29, 2007 Share Posted January 29, 2007 Take a step back. is the OBD2 interface MORE complicated (more inputs / more outputs) than an OBD1? If so, then an ECU using an OBD2 INTERFACE will be using MORE inputs and more outputs; hence you will find OBD2 based ECUs in newer cars rather than older cars (for all the reasons that I mentioned earlier). Yes OBDII does expose more features of the ECU, however, OBDII is not what it used to connect up to the engine. It is purely a diagnosis interface specification. By default anything with OBDII will be a new design ECU, since they have to adopt the new standards. And as far OBDII, it pretty much has two wires, a K line and an L Line Quote Link to comment Share on other sites More sharing options...
sdavies Posted January 29, 2007 Share Posted January 29, 2007 Take a step back. is the OBD2 interface MORE complicated (more inputs / more outputs) than an OBD1? If so, then an ECU using an OBD2 INTERFACE will be using MORE inputs and more outputs; hence you will find OBD2 based ECUs in newer cars rather than older cars (for all the reasons that I mentioned earlier). OBD1 & OBD2... I think what is being said, is you are possibly clouding the purer side of the question - OBD is fook all to do with the model of ECU, you could in theory have an ultra modern ECU with OBD1... or an RS232(432)/whatevah! interface that conforms to some other standard. But as you say, things move with the times. I am guessing the Honda tunin boyz say - OBD1 = easy tune, OBD2 means you have the twatting hard ECU to tune? Quote Link to comment Share on other sites More sharing options...
imi Posted January 29, 2007 Share Posted January 29, 2007 Yes OBDII does expose more features of the ECU, however, OBDII is not what it used to connect up to the engine. It is purely a diagnosis interface specification. By default anything with OBDII will be a new design ECU, since they have to adopt the new standards. And as far OBDII, it pretty much has two wires, a K line and an L Line OK, I get you now...I was referring to the newer OBD2 (on-board diag) having a direct correlation on the design of the ECU (16bit, etc) and hence harder to tune for all the reasons mentioned earlier. maybe its not so bad on the supras...although I have heard that the non-VVTi's are easier to tune than the VVTi.... Quote Link to comment Share on other sites More sharing options...
JustGav Posted January 29, 2007 Share Posted January 29, 2007 OK, I get you now...I was referring to the newer OBD2 (on-board diag) having a direct correlation on the design of the ECU (16bit, etc) and hence harder to tune for all the reasons mentioned earlier. maybe its not so bad on the supras...although I have heard that the non-VVTi's are easier to tune than the VVTi.... Strictly speaking there is no difference with the tuning on either, it is just more common to do the non-vvti's. Things such as the plug and play AEM aren't available for it, however there are plenty of options with available. Gav Quote Link to comment Share on other sites More sharing options...
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