2JZGE Na-T TT Ecu Mod
10-15-15, 08:57 AM
#2851
Did you mention that your settings have been adjusted on the safc? What are your idle settings now % fuel pulled? Reset the ecu by pulling the neg battery cable, take it for a drive and after a day or so see if it's still doing it. Normally a battery reset causes the tune to be weird for a little bit till it relearns. I would double check your connections in the foot well, make sure the wiring is sound.
Thanks!
10-15-15, 09:35 PM
#2853
these ecu's do want to idle at like 650 rpm and they wont go that low until its fully warmed up.
I would suggest simplifying.
If you are having the idle lower than 650, you can try bumping up the idle but you will need to turn the tps back some and there is only a small amount of adjustment. most people end up raising the idle screw at least a hair to let a little more air in to stabilize things. but still it has to be in tps range, you can check by trying to do the timing check procedure, if it changes in noise when you put the jumper in, tps is still in correct spot. on the first page.
I would suggest simplifying.
If you are having the idle lower than 650, you can try bumping up the idle but you will need to turn the tps back some and there is only a small amount of adjustment. most people end up raising the idle screw at least a hair to let a little more air in to stabilize things. but still it has to be in tps range, you can check by trying to do the timing check procedure, if it changes in noise when you put the jumper in, tps is still in correct spot. on the first page.
So I was having this weird issue with cold starts, car wouldn't want to rev, it would sputter and hesitate if I blipped the throttle. Once warm it would clear up, but still would slightly be there.
I tried to raise idle from 650 to 800-900ish via manual adjustment to the idle set screw on the throttle body which messed up the TPS setting. I tried to fool the stock ECU into getting a higher RPM but it wasn't having it.
Returned the idle set screw back to stock, reset the ecu, car now purrs smooth at 650rpm without any hesitation. I'm gonna stop fighting it and just let it do it's thing, car runs fine that low of RPM which is crazy because my old DSM would struggle to idle at anything below 750.
I say this now but watch me jinx it and it do it tomorrow lol. I purchased new ignition components thinking maybe a spark plug fouled or possibly a coil pack? Saved me from tearing the intake manifold down.
10-16-15, 02:50 PM
#2855
yeah moving the idle screw is not for the faint of heart.. lol, it can create problems also if you dont know how to check the tps. they should make a tps with wider slots, that would solve our issues on that front with the stock throttle body, my mcguiver side says just get a spare tps and slot out the sides and use washers to grab it down, but then again its pretty mcghuivered.
SG, glad its working, keep an eye on it, if it starts acting up again after 4-5 drives then its likely the safc.
SG, glad its working, keep an eye on it, if it starts acting up again after 4-5 drives then its likely the safc.
10-20-15, 03:34 PM
#2859
I already have the full top section off except the Plenum part which mates to the runner. I took every bolt out but that little black bracket keeps all those hard lines on there. They are all very rigid so I'm just going to hack at it most likley.. because its a waste of time at this point.
10-22-15, 06:57 AM
#2861
Thanks again for all of the help in this thread! This mod is Awesome!
The car is an absolute blast to drive. I am starting to really trust and understand the car. Most times when the AFR's look different at idle, it straightens right out when I drive it. I am starting to not worry about them so much at idle.
The only thing I notice now is after running the car for a couple hours, the idle gets slightly rough and rich (or lean occasionally). I sometimes shut it off, and back on at a light and it fixes itself. Just driving it, it generally works itself out. If I park it for a few minutes and start it back up warm, the idle may still be a bit "off". When it is "off", the rhythm of the car is also a bit off and usually rich but sometimes lean. During these times, I also hear a mild "diesel" sound to the motor occasionally as idle drops and fluctuates. There is a mild "surging" of idle a few hundred RPM's, every second or so in a constant pulse.
This is very minor/mild but I am trying to understand and respond to all clues given to me by the car. I also noticed much of this after my friend's feet shorted out the ECU wiring and blew the EFI fuse. I am going to send my spare Aristo ECU to Driftmotion to rebuild it. I'll swap that in to see if anything is different. I get the feeling although the caps were replaced, my current ECU may be slightly bad. It will be informative to be able to swap them out when troubleshooting. I may even look for a 6 speed JDM version as a third.
It runs perfectly at all times except when the idle gets a bit strange after a few hours running it in NYC traffic. Temps are rock solid at all times. On boost AFR's are always consistent.
The car is an absolute blast to drive. I am starting to really trust and understand the car. Most times when the AFR's look different at idle, it straightens right out when I drive it. I am starting to not worry about them so much at idle.
The only thing I notice now is after running the car for a couple hours, the idle gets slightly rough and rich (or lean occasionally). I sometimes shut it off, and back on at a light and it fixes itself. Just driving it, it generally works itself out. If I park it for a few minutes and start it back up warm, the idle may still be a bit "off". When it is "off", the rhythm of the car is also a bit off and usually rich but sometimes lean. During these times, I also hear a mild "diesel" sound to the motor occasionally as idle drops and fluctuates. There is a mild "surging" of idle a few hundred RPM's, every second or so in a constant pulse.
This is very minor/mild but I am trying to understand and respond to all clues given to me by the car. I also noticed much of this after my friend's feet shorted out the ECU wiring and blew the EFI fuse. I am going to send my spare Aristo ECU to Driftmotion to rebuild it. I'll swap that in to see if anything is different. I get the feeling although the caps were replaced, my current ECU may be slightly bad. It will be informative to be able to swap them out when troubleshooting. I may even look for a 6 speed JDM version as a third.
It runs perfectly at all times except when the idle gets a bit strange after a few hours running it in NYC traffic. Temps are rock solid at all times. On boost AFR's are always consistent.
Last edited by Studiogeek; 10-22-15 at 09:18 AM.
10-23-15, 09:01 AM
#2863
I finally figured out why my car was running mad rich and shutting off once it got to normal running temperature.
It was the crappy eBay injectors! I swapped them out for a set of Osidetiger 440cc and now it idles fine. Before this.. I sent out the ecu, tripled checked wiring, plugs, dis., map sensor, igniter.... This is huge for me.
Now I'm trying to set the timing but there is no audible change when I put in the jumper. Guess I should take a break and grab a beer.
It was the crappy eBay injectors! I swapped them out for a set of Osidetiger 440cc and now it idles fine. Before this.. I sent out the ecu, tripled checked wiring, plugs, dis., map sensor, igniter.... This is huge for me.
Now I'm trying to set the timing but there is no audible change when I put in the jumper. Guess I should take a break and grab a beer.
10-23-15, 09:06 AM
#2864
Great news! TPS isn't set correctly if you aren't hearing the idle change when the jump is inserted.
So I was reading about swapping to an OBDII ecu and you have to wire in a ground for the heated O2 circuit. The reason they went to a heated O2 sensor was due to the fact that the non heated OBD1 sensors would sometimes loose their heat or cool off during times of long idling. This causes the tune to go off and richens the mixture. Once you drive off the exhaust heats the sensor and fixes the issue.
So I was thinking could adding a heated O2 sensor and add a ground make the tune more consistent? Is this a fairly simple upgrade, purchase O2 sensor, rewire it in, add ground?
So I was reading about swapping to an OBDII ecu and you have to wire in a ground for the heated O2 circuit. The reason they went to a heated O2 sensor was due to the fact that the non heated OBD1 sensors would sometimes loose their heat or cool off during times of long idling. This causes the tune to go off and richens the mixture. Once you drive off the exhaust heats the sensor and fixes the issue.
So I was thinking could adding a heated O2 sensor and add a ground make the tune more consistent? Is this a fairly simple upgrade, purchase O2 sensor, rewire it in, add ground?
Last edited by HiPSI; 10-23-15 at 09:13 AM.
10-23-15, 10:11 AM
#2865
Great news! TPS isn't set correctly if you aren't hearing the idle change when the jump is inserted.
So I was reading about swapping to an OBDII ecu and you have to wire in a ground for the heated O2 circuit. The reason they went to a heated O2 sensor was due to the fact that the non heated OBD1 sensors would sometimes loose their heat or cool off during times of long idling. This causes the tune to go off and richens the mixture. Once you drive off the exhaust heats the sensor and fixes the issue.
So I was thinking could adding a heated O2 sensor and add a ground make the tune more consistent? Is this a fairly simple upgrade, purchase O2 sensor, rewire it in, add ground?
So I was reading about swapping to an OBDII ecu and you have to wire in a ground for the heated O2 circuit. The reason they went to a heated O2 sensor was due to the fact that the non heated OBD1 sensors would sometimes loose their heat or cool off during times of long idling. This causes the tune to go off and richens the mixture. Once you drive off the exhaust heats the sensor and fixes the issue.
So I was thinking could adding a heated O2 sensor and add a ground make the tune more consistent? Is this a fairly simple upgrade, purchase O2 sensor, rewire it in, add ground?