na-t GTE ecu project wont boost past 4k
08-08-12, 08:29 PM
#1
na-t GTE ecu project wont boost past 4k
So i threw an xs power kit on my car, everything went smoothly and as expected.
For engine management im by no means rich enough to pay the tuners around here 600+ for a tune that they wont gurantee runs good because they say that i need an AEM.
so heres what im using
-obd1 aristo ECU
-vvti coils and igniter
- TT pump
-TT spark plugs
Basically im getting a code 31 for map sensor voltage and my car wont really boost past 4k.... it just falls on its face.
The car is running super rich, already fouled out my brand new TT plugs and i use about 3x the normal amount of fuel, actually used 1/4 tank in 20 miles and the whole rear of my car is black.
The pin 62 map signal wire is reading a little over 4 volts, according to sources (ali and others) its supposed to read 2.4 with key on engine off, and i cant seem to figure it out.
Ive already replaced the map sensor and the ECU itself to no avail, also just tried running a fresh map signal wire straight from the ECU and still no luck.
Can anyone help me out here?? My boy seems to think its something with the fuel pressure regulator because for some reason there is no vacuum at the FPR,
But im not sure why this would all of the sudden if my car was running great pre- turbo install. Even in neutral revving the car up there is no vacuum at the FPR.
Not sure if this is related but definetely wanted to note it.
so again, can anyone point me in the right directiom? im out of ideas?
feel free to ask me as many questions as needed or throw any ideas out there cause im stumped
For engine management im by no means rich enough to pay the tuners around here 600+ for a tune that they wont gurantee runs good because they say that i need an AEM.
so heres what im using
-obd1 aristo ECU
-vvti coils and igniter
- TT pump
-TT spark plugs
Basically im getting a code 31 for map sensor voltage and my car wont really boost past 4k.... it just falls on its face.
The car is running super rich, already fouled out my brand new TT plugs and i use about 3x the normal amount of fuel, actually used 1/4 tank in 20 miles and the whole rear of my car is black.
The pin 62 map signal wire is reading a little over 4 volts, according to sources (ali and others) its supposed to read 2.4 with key on engine off, and i cant seem to figure it out.
Ive already replaced the map sensor and the ECU itself to no avail, also just tried running a fresh map signal wire straight from the ECU and still no luck.
Can anyone help me out here?? My boy seems to think its something with the fuel pressure regulator because for some reason there is no vacuum at the FPR,
But im not sure why this would all of the sudden if my car was running great pre- turbo install. Even in neutral revving the car up there is no vacuum at the FPR.
Not sure if this is related but definetely wanted to note it.
so again, can anyone point me in the right directiom? im out of ideas?
feel free to ask me as many questions as needed or throw any ideas out there cause im stumped
08-08-12, 10:31 PM
#2
not sure if this helps but when i did a jdm 2jz aristo swap it would feel like i would hit a brick wall at 4k rpms but when normal driving without boost it does it would run fine. it was only when i'm in boost it would hit 4k brick wall feeling.
installed a greddy boost cut controller and problem was gone. for me the problem was the aristo ecu has a boost cut at 4k rpms if your overboosing more than stock psi. also the check engline would turn on but it would turn off right when i get out of boost.
i'm located in the bay area also Goodluck!
installed a greddy boost cut controller and problem was gone. for me the problem was the aristo ecu has a boost cut at 4k rpms if your overboosing more than stock psi. also the check engline would turn on but it would turn off right when i get out of boost.
i'm located in the bay area also Goodluck!
08-09-12, 07:49 AM
#3
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What MAP sensor are you running? Your GE ECU will not read a turbo MAP sensor. You will need to run a piggyback, or like your tuners mentioned, go stand alone.
That's not entirely true...Aristo ECU's have a boost cut at 17~18psi. As long as you keep your boost levels under that, you'll be fine. If you are still running factory sequential twins, and boosting over 17psi, you'll go into low boost mode.
not sure if this helps but when i did a jdm 2jz aristo swap it would feel like i would hit a brick wall at 4k rpms but when normal driving without boost it does it would run fine. it was only when i'm in boost it would hit 4k brick wall feeling.
installed a greddy boost cut controller and problem was gone. for me the problem was the aristo ecu has a boost cut at 4k rpms if your overboosing more than stock psi. also the check engline would turn on but it would turn off right when i get out of boost.
i'm located in the bay area also Goodluck!
installed a greddy boost cut controller and problem was gone. for me the problem was the aristo ecu has a boost cut at 4k rpms if your overboosing more than stock psi. also the check engline would turn on but it would turn off right when i get out of boost.
i'm located in the bay area also Goodluck!
Last edited by TweakTech; 08-09-12 at 08:00 AM.
08-09-12, 08:39 AM
#4
hes running a JDM 2jzgte aristo ecu exactly like what I am running on my na-t.
It uses a map sensor for fueling. there is no possible way you are hitting boost cut that low.
when you have a map sensor code, the ecu limits itself to that engine speed. there is nothing wrong with your ecu. Sj408 you have a short somewhere, did you run a new signal line.
also follow the diagram exactly both the grounds go to the ground on pin 1. not one to each brown wire.
It uses a map sensor for fueling. there is no possible way you are hitting boost cut that low.
when you have a map sensor code, the ecu limits itself to that engine speed. there is nothing wrong with your ecu. Sj408 you have a short somewhere, did you run a new signal line.
also follow the diagram exactly both the grounds go to the ground on pin 1. not one to each brown wire.
08-09-12, 11:27 AM
#5
What MAP sensor are you running? Your GE ECU will not read a turbo MAP sensor. You will need to run a piggyback, or like your tuners mentioned, go stand alone.
That's not entirely true...Aristo ECU's have a boost cut at 17~18psi. As long as you keep your boost levels under that, you'll be fine. If you are still running factory sequential twins, and boosting over 17psi, you'll go into low boost mode.
That's not entirely true...Aristo ECU's have a boost cut at 17~18psi. As long as you keep your boost levels under that, you'll be fine. If you are still running factory sequential twins, and boosting over 17psi, you'll go into low boost mode.
My problem is that the map signal wire is reading 4.xx volts at key on engine off which is supposed to be 2.4
Ali thinks it could be because im using a non-ecu ground for the map, ill have to test tonight?
Ive replaced the ecu and the map and neither helped, so it must be in the wiring? what do you think tweak?
hes running a JDM 2jzgte aristo ecu exactly like what I am running on my na-t.
It uses a map sensor for fueling. there is no possible way you are hitting boost cut that low.
when you have a map sensor code, the ecu limits itself to that engine speed. there is nothing wrong with your ecu. Sj408 you have a short somewhere, did you run a new signal line.
also follow the diagram exactly both the grounds go to the ground on pin 1. not one to each brown wire.
It uses a map sensor for fueling. there is no possible way you are hitting boost cut that low.
when you have a map sensor code, the ecu limits itself to that engine speed. there is nothing wrong with your ecu. Sj408 you have a short somewhere, did you run a new signal line.
also follow the diagram exactly both the grounds go to the ground on pin 1. not one to each brown wire.
Last edited by sj408; 08-09-12 at 12:32 PM.
08-10-12, 07:03 AM
#7
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Do you have a CEL of any kind? Also, are you using your original GE harness modified for MAP/IAT, and coil packs, or are you using a GTE harness? Which VVTi engine did you get your coil packs from?
Spark plugs...have you tried running a colder plug? I'd throw some NGK 7s, or 8s in there. With as rich as you're running, you might be extinguishing the spark before the engine air/fuel charge can combust. If you pull the plug out of the chamber a little, it will allow the ignition of the charge to "spread" better across the chamber. I ran into that issue with my old Turbo Honda project. I ended up running a set of 8s, and it fixed my problem.
Spark plugs...have you tried running a colder plug? I'd throw some NGK 7s, or 8s in there. With as rich as you're running, you might be extinguishing the spark before the engine air/fuel charge can combust. If you pull the plug out of the chamber a little, it will allow the ignition of the charge to "spread" better across the chamber. I ran into that issue with my old Turbo Honda project. I ended up running a set of 8s, and it fixed my problem.
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08-10-12, 10:10 AM
#8
he has a CEL for the map sensor and it is not reading the right voltage, so I would say its a map sensor problem.
It is not a fault of the ignition, the ECU limits the rpm's when it gets a map sensor code.
once the code is gone it will run normally.
see below straight from the manual.
It is not a fault of the ignition, the ECU limits the rpm's when it gets a map sensor code.
once the code is gone it will run normally.
see below straight from the manual.
08-10-12, 10:19 AM
#9
did you change anything on your Main TPS by any chance? it should be left stock.
what brand IAT are you running and next time you fire it up try unplugging the IAT.
also If you have trac control, I want you to unplug your trac control tps, and then fire it up.
just trying to eliminate all things on the sensor circuit that I can think of that you may have that I dont.
Six sense has a manual car like me so no trac control, its a stretch but maybe its something silly like that.
what brand IAT are you running and next time you fire it up try unplugging the IAT.
also If you have trac control, I want you to unplug your trac control tps, and then fire it up.
just trying to eliminate all things on the sensor circuit that I can think of that you may have that I dont.
Six sense has a manual car like me so no trac control, its a stretch but maybe its something silly like that.
08-10-12, 10:46 AM
#10
Ok so after talking with SJ408, we think the 2 outer pins on the map sensor need to be swapped.
the diagrams that were posted were not too clear on exactly which pin goes where, but im pretty sure that is.
I will try and make a new diagram unless 8052jz beats me to it.
the diagrams that were posted were not too clear on exactly which pin goes where, but im pretty sure that is.
I will try and make a new diagram unless 8052jz beats me to it.
08-10-12, 11:48 AM
#12
K so fixed the map wiring and it runs 100x better, with some clean plugs this thing is 100% driveable..... until 4k rpms. still falls flat on its face at 4k.
also still have code 31 even after immediate reset and not starting the engine yet
also still have code 31 even after immediate reset and not starting the engine yet
08-10-12, 01:58 PM
#14
Pulled the battery cable and efi fuse to reset and before i even started the car it threw a code 31.
Im stumped, Think it could need a bcc like suggested above? my boss who has had 2 supras seems to agree. I just dont know why i would always have a map code.
It does run 100x better with map sensor hooked up correctly now.... no more dumping smoke like a diesel and seems to drive a ton better. But still no boost past 4k rpms
08-10-12, 02:07 PM
#15
