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NOSUP4U
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Discussion Starter #41
good grief... you need an AirFlow Meter... :chairshot
Well I have never seen nor heard of any JDM ECU equipped 2jz needing an airflow meter, just the map sensor..so i dont believe thats the problem..thanks anyways

So you went from JDM injectors to 550s and there was no change? Did you pull the plugs to check if all cylinders are fouling out?
Yea, i initially started it with the JDM 440s and then swapped it out for USDM 550s with resistor,and the problem is still the same. I have even changed out stock regulators. All of the cylinders are firing and all my plugs are dark as night from running so rich...the AFRs stay pegged at 10.0
 

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Well, you 100% DO NOT need a MAF as you probably figured out by now. When you hook the safc up, are you getting map and TPS readings? Stupid question, but when you went back with 440s, you removed the resistor box, right?
 

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NOSUP4U
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Discussion Starter #43
Yea I figured I didnt need a MAF. I havent checked the SAFC for those readings, guess I should. As for the injectors. I started out with the 440s without resistor box, and then when i got my 550s in a week later, did the wiring for the resistor, and put the 550s in and it did the same thing.
 

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Do you have the intake air temp sensor wired up right? The JDM ecu needs both the air temp and the map sensor in order to make correct airflow calculations.
 

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Japanese Tuning in Plain English

Well I have never seen nor heard of any JDM ECU equipped 2jz needing an airflow meter, just the map sensor..so i dont believe thats the problem..thanks anyways
Yea, i initially started it with the JDM 440s and then swapped it out for USDM 550s with resistor,and the problem is still the same. I have even changed out stock regulators. All of the cylinders are firing and all my plugs are dark as night from running so rich...the AFRs stay pegged at 10.0
Well, you 100% DO NOT need a MAF as you probably figured out by now. When you hook the safc up, are you getting map and TPS readings? Stupid question, but when you went back with 440s, you removed the resistor box, right?
Do you have the intake air temp sensor wired up right? The JDM ecu needs both the air temp and the map sensor in order to make correct airflow calculations.
I can answer that... No, he doesn't. How can I know this? Because the Intake Air Temperature Sensor is located in the AFM... and he doesn't have an AFM.

Let me bring you boys up to speed with a more simplfied explaination.... JDM and USDM ECU's requires at least 6 input sensors to determine correct injection volume and injection timing. This is a fact.... not my opinion.

Intake Air Volume - AFM sensor
Intake Air Temperature - IAT sensor
Engine Speed - Crank Position sensor
Manifold Air Pressure - MAP sensor
Engine Coolant Temperature - ECT sensor
Exhaust Oxygen Content - O2 sensor

Remove any one of these sensors and your car will run like shit. You will also have a DTC or "check engine" light on for that particular sensor.

Choritsu-shi
 

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Choritsu-shi, his engine does not have or need an AFM. It is a MAP based engine...

Greg, how much vacuum are you pulling at idle? Also, you can verify map and tps signal with the SAFC connected? Where does it idle RPM-wise?
 

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Error code 31 on the JZS147 is MAP sensor related, which makes sense. Since you have replaced the map sensor already, it could be the wiring between MAP and ECU, OR, you could have a dirt dobber nest in your map vacuum hose :) Have you checked the map hose to make sure it is clear and sending vac/boost signal?
 

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I can answer that... No, he doesn't. How can I know this? Because the Intake Air Temperature Sensor is located in the AFM... and he doesn't have an AFM.
Choritsu-shi
On the JDM (non-vvti) engine, the Intake Air Temp (IAT) sensor is located on the intake manifold, right near the map sensor. As has been mentioned before this engine does not use an AFM. The JDM vvti 2jz does, both NA 2jz engines do, and the USDM 2jz does, but not the non-vvti JDM engine.

I can personally verify that my aristo engine harness has no plug for a MAF, and has the IAT sensor screwed into the intake manifold and is wired as such.

The IAT sensor also shares a ground with the MAP sensor, so an issue with that could possibly cause a MAP code.
 

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Good info regarding the IAT JonoTurbo. This could also be a simple case of bad ECU. Have you opened the ecu up and looked for popped caps? A known good ecu to try would be nice...
 

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NOSUP4U
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Discussion Starter #50
The two things I will be checking tomorrow when i get my buddy to come over with his complete JDM motor, are the ECU and IAT. I really hope one of the two fixes my problem :/ Really want to drive my car!!! Thanks for all the responses guys, I will keep you updated!
 

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On the JDM (non-vvti) engine, the Intake Air Temp (IAT) sensor is located on the intake manifold, right near the map sensor. As has been mentioned before this engine does not use an AFM. The JDM vvti 2jz does, both NA 2jz engines do, and the USDM 2jz does, but not the non-vvti JDM engine.

I can personally verify that my aristo engine harness has no plug for a MAF, and has the IAT sensor screwed into the intake manifold and is wired as such.

The IAT sensor also shares a ground with the MAP sensor, so an issue with that could possibly cause a MAP code.
Okay... I 've been wrong before. I have seen an additional sensor located on the intake manifold before... but not sure what it was.

Choritsu-shi
 

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Okay... I 've been wrong before. I have seen an additional sensor located on the intake manifold before... but not sure what it was.

Choritsu-shi
yes i think you are talking about the other intake sensor with a nipple on it that is suppose to have a vac line ran from that to your turbo intake pipe... "i think"
 

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NOSUP4U
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Discussion Starter #55
So i have swapped out ECU's, checked all the sensors, and traced all the wiring to the ecu plugs, and everything is in order..WTF is going on with my car???? I am clueless at this point
 

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NOSUP4U
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Discussion Starter #57
nothing changes :(
 

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NOSUP4U
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Discussion Starter #59
taking negative terminal off for atleast 30 seconds resets ecu? correct? if so, yes numerous times
 

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Na-T
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damn greg, I hope you get the car on the road quick. ITs been down forever.
 
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