GTR Fever Posted April 9, 2015 Share Posted April 9, 2015 Hi everyone, Been looking around at ECU options as they might sort out some gremlins I have in my Supra still (Aristo swap done 5 years ago and still has issues ) Tuner recommended the AEM V2 that's designed/ upgraded for Auto as he can fiddle with the idle RPM and might even be able to fix the A/C idle-up issue through there. About a year ago I installed an HKS FCD to get rid of the boost cut that happens since the exhaust upgrade (has the restrictor ring for 15-16psi). Boost cut is gone, but the engine check light still comes on when running WOT for a while. Once you switch off and restart, check light is gone. All those things tuner claimed to be able to fix with the ECU upgrade. I know it's a costly upgrade but if it will mean I can comfortably enjoy my MKIV then I will most likely do it. What are your thoughts on this? Anyone has experience with the AEM V2 in their Auto Supra?? Thanks in advance, Chris. Quote Link to comment Share on other sites More sharing options...
mellonman Posted April 9, 2015 Share Posted April 9, 2015 Mate that warning light that comes on at WOT is engine knock / det control , do you have an upgraded fuel pump ? and have you gone full bpu , click on bpu if you dont know what it is I would get your tuning to have a look at what afr your running when WOT to make sure you dont have an issue , as for the ecu there are better ones out there but if thats what your mapper is comfortable with then it will save you money in the long run Quote Link to comment Share on other sites More sharing options...
Abz Posted April 9, 2015 Share Posted April 9, 2015 My car is a NA - TT swap with a VVTi engine and I have never had any issues, runs just as sweet as my previous Supra if not better. It seems the swap as not been done correctly with very little knowledge. I noticed in another thread you mentioned that you were still using an Aristo ECU. Do you have anymore information on the loom used and list of problems you do have? The AEM might be one way to fix it but it sounds like you have an underlining of issues, I would look at then one by one. Quote Link to comment Share on other sites More sharing options...
GTR Fever Posted April 9, 2015 Author Share Posted April 9, 2015 Thanks for the responses. The fuel pump is an aeromotive stealth 340lph but I have not done any 12V fuel pump mod, is this necessary? Abz, yes I am still using the Aristo ECU. The swap was done by local "2JZ experts" and I am trying to correct the issues known. I know for a fact that the Aristo ECU and engine loom was used, dash loom was not removed/ changed. Issues after the swap: 1. Tach did not work: Fixed using an MSD tach adapter 2. A/C did not engage: Fixed by using the pinout diagrams about 5 years ago 3. A/C idle-up does not work at all - Still outstanding 4. Cruise control does not work (not important to me) 5. Overdrive button does not work (light comes on the cluster but it does not actually affect the transmission) - at first the car had no overdrive at all because it was not wired, fixed that so all gears change now, just not controlled by the button on the shifter 6. Cold start idle is horrible and will stall if RPM not held for a while for the engine to build some heat 7. Alternator was not wired properly (aristo and supra have different plugs): Fixed this myself and installed a higher current alternator 8. Engine check like at WOT: it comes on after I come off the accelerator, no hesitation for power, no weird noises etc so I'm not sure what's the problem That is all I can think of for now. Quote Link to comment Share on other sites More sharing options...
GTR Fever Posted April 9, 2015 Author Share Posted April 9, 2015 Regarding the BPU, here is the list of mods: 3" thick front mount intercooler with piping Greddy intake system 3.5" exhaust with restrictor ring (fully decatted) Aeromotive stealth 340LPH fuel pump Colder grade plugs (not sure what grade, but they will be changed to HKS plugs soon) HKS FCD, can't remember what number it is set at but I can check it other than that: Bilstein TT struts with Tein S-tech springs Mishimoto radiator (3 core) Mishimoto radiator hoses Mishimoto transmission cooler TiAL blowoff valve Quote Link to comment Share on other sites More sharing options...
Big Supes Posted April 9, 2015 Share Posted April 9, 2015 Regardless of your problems, if you have the option to go with a mappable ECU, do it. The FCD is a crude way around upping the boost, IMO. For this reason, I'm looking to do the same. BTW, what number do you have the FCD set to? Quote Link to comment Share on other sites More sharing options...
GTR Fever Posted April 10, 2015 Author Share Posted April 10, 2015 But will it fix all my issues? If it will, I will definitely look into the programmable ECU. FCD is set to 9 and works pretty good. After reading up on the function of the FCD I know it's a crude way but it stopped the boost spike/ fuel cut issue I had. Quote Link to comment Share on other sites More sharing options...
David P Posted April 10, 2015 Share Posted April 10, 2015 (edited) Thanks for the responses. The fuel pump is an aeromotive stealth 340lph but I have not done any 12V fuel pump mod, is this necessary? Abz, yes I am still using the Aristo ECU. The swap was done by local "2JZ experts" and I am trying to correct the issues known. I know for a fact that the Aristo ECU and engine loom was used, dash loom was not removed/ changed. Issues after the swap: 1. Tach did not work: Fixed using an MSD tach adapter 2. A/C did not engage: Fixed by using the pinout diagrams about 5 years ago 3. A/C idle-up does not work at all - Still outstanding 4. Cruise control does not work (not important to me) 5. Overdrive button does not work (light comes on the cluster but it does not actually affect the transmission) - at first the car had no overdrive at all because it was not wired, fixed that so all gears change now, just not controlled by the button on the shifter 6. Cold start idle is horrible and will stall if RPM not held for a while for the engine to build some heat 7. Alternator was not wired properly (aristo and supra have different plugs): Fixed this myself and installed a higher current alternator 8. Engine check like at WOT: it comes on after I come off the accelerator, no hesitation for power, no weird noises etc so I'm not sure what's the problem That is all I can think of for now. 1. Bridging the resistor would have done that. 2. Sorted (for now) 3. It never will with an Aristo ECU. 2, 3, 4, 5, 6 would be fixed by using a Supra T.T. ECU. 7. Sorted. 8. Gary's onto that one. http://www.mkivsupra.net/vbb/showthread.php?303221-AEM-FIC-Fix-and-or-GE-Coil-Pack-Conversion Edited July 14, 2015 by David P (see edit history) Quote Link to comment Share on other sites More sharing options...
mellonman Posted April 10, 2015 Share Posted April 10, 2015 In regards to the engine light at WOT, this does sound like knock control the ecu will pull timing and goes into limp mode IIRC, I dont think you notice anything to drastic power wise have you checked the fault codes , im not sure if they still would be output correctly with not having the correct dash loom for the ecu ? but well worth a try to see if it has stored a code Quote Link to comment Share on other sites More sharing options...
GTR Fever Posted April 13, 2015 Author Share Posted April 13, 2015 David thanks a mil for a detailed response! The tach mod will fix what issue exactly? Not really good with electrical stuff, better on the mechanical side but I'll take a go at it if needed. I pulled the codes years ago but cannot remember. Will pull the codes next time around for sure. Now where do I find a TT Auto ECU? Will the UK and JDM be the same? Once I get the car working right I will be happy, not in it for big power or a race car. In our climate, A/C is very important lol...averages 34 degrees celcius with really high humidity. By the way, I do not drive the car often at all (mainly due to current issues) so within the past 5-6 years, I have put on around 2500-3500km Quote Link to comment Share on other sites More sharing options...
David P Posted April 13, 2015 Share Posted April 13, 2015 You're welcome. The tach mod would have been a free way to not buy an MSD tach adaptor. I believe you need a JDM auto ECU, pm Keron who will confirm and may even have one you could buy, if not, put up an add in the Wanted page. http://www.mkivsupra.net/vbb/member.php?676-keron Quote Link to comment Share on other sites More sharing options...
GTR Fever Posted April 14, 2015 Author Share Posted April 14, 2015 PM'd If he cannot help me I will post the ad. Exploring the option to get a new ECU out of Japan as well. Have an uncle who lives there but he is unable to hunt around for used parts due to age and mobility but he gets new parts from the dealers. Planning to take the Supra out for a spin at the end of the month, want to sort out as much gremlins as possible, do-over my interior then finish up with the body work I have planned (already got all the parts I need) Quote Link to comment Share on other sites More sharing options...
GTR Fever Posted June 3, 2015 Author Share Posted June 3, 2015 Hey guys, I am getting a JDM TT ecu but I have another question/ convern... An electrician came to my shop a few years ago and did SOMETHING for the AC to engage. From what I read, the Aristo and Supra ECU's send different signals. Will changing to a Supra ECU now cause a problem with this? Should I correct what he did first? Thanks in advance. Quote Link to comment Share on other sites More sharing options...
GTR Fever Posted July 13, 2015 Author Share Posted July 13, 2015 So i installed the Supra ECU and the car starts and idles a little better IMO (might be mind over matter) but the A/C does not engage at all. I am sure it has to do with the wiring changes done by previous electrician for the compressor to engage. I checked the wiring near the ECU and discovered a relay wired in which clicks when the A/C switch is turned on. However I also noticed ALOT of other unconnected wires. So much that I decided to tape them up carefully, re-install the Aristo ECU and get in contact with a "good" electrician who did some work on my Subaru recently. He's trying to locate the wiring diagram for the 1993 NA JDM Supra (not ECU pinouts, body wiring) and he will attempt to re-wire the engine install using the Supra ECU I got. It sucks yes, especially seeing that this "wiring" was done by one of the local 2JZ experts. Oh well, I just want my car working right. Any advice? Quote Link to comment Share on other sites More sharing options...
thomo8568 Posted July 13, 2015 Share Posted July 13, 2015 So i installed the Supra ECU and the car starts and idles a little better IMO (might be mind over matter) but the A/C does not engage at all. I am sure it has to do with the wiring changes done by previous electrician for the compressor to engage. I checked the wiring near the ECU and discovered a relay wired in which clicks when the A/C switch is turned on. However I also noticed ALOT of other unconnected wires. So much that I decided to tape them up carefully, re-install the Aristo ECU and get in contact with a "good" electrician who did some work on my Subaru recently. He's trying to locate the wiring diagram for the 1993 NA JDM Supra (not ECU pinouts, body wiring) and he will attempt to re-wire the engine install using the Supra ECU I got. It sucks yes, especially seeing that this "wiring" was done by one of the local 2JZ experts. Oh well, I just want my car working right. Any advice? http://wilbo666.pbworks.com/w/page/41678224/2JZ-GE%20JZA80%20Supra Quote Link to comment Share on other sites More sharing options...
David P Posted July 13, 2015 Share Posted July 13, 2015 Join the wires back together, colour to colour. Quote Link to comment Share on other sites More sharing options...
Ian C Posted July 14, 2015 Share Posted July 14, 2015 Join the wires back together, colour to colour. If only all problems had such a simple solution Quote Link to comment Share on other sites More sharing options...
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