Apexi AFC Neo Help! Car Starts, Rough Idle, Then Stall
02-25-09, 11:04 PM
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Apexi AFC Neo Help! Car Starts, Rough Idle, Then Stall **Finally Solved**
UPDATE! Problem Solved!
Okay, the solution was pretty simple. INSTEAD of using the black/white and brown/white wires, USE THE YELLOW AND WHITE wires. Once you have those setup. USE HOTWIRE INSTEAD OF KARMAN.
My check engine light went away and my car actually runs!
It might be because of the new style MAF's on the 96's.
Original Post:
So I bought a brand new Apexi AFC Neo off a member on the supra forums last week. I go to install it on my 96 SC400, and the car doesn't want to stay on. I checked all the cables, everything seems to be connected fine.
I wired it EXACTLY as shown here:
And used the T7-a ECU diagram:
Everything is connected like exactly as shown above. I turned the key to the ON position, initialized the system, set it to 4 Cylinders, set the throttle from 0-5V, set it Karman Sensor, and V/T OFF.
So far, the AFC turns on, there is input from the throttle, it reads the RPMs, and it can read the battery voltage.
The Problem: When I go start the car, it starts, goes to about 2000 rpm, then kind of wobbles and Stalls. Ive tried this at least 5 times messing with the cables making sure its properly connected; same thing.
The car even threw a Check Engine Light CEL: P0100 Mass Air Flow (MAF) Circuit Malfunction.
http://www.obd-codes.com/p0100
Here is a pic of the sensor check while in the ON key position but the car off:
At this point, I don't know what to do. Everything seems like its connected fine to me.
Someone please help me before I put this thing back in the box.
-David
Okay, the solution was pretty simple. INSTEAD of using the black/white and brown/white wires, USE THE YELLOW AND WHITE wires. Once you have those setup. USE HOTWIRE INSTEAD OF KARMAN.
My check engine light went away and my car actually runs!
It might be because of the new style MAF's on the 96's.
Original Post:
So I bought a brand new Apexi AFC Neo off a member on the supra forums last week. I go to install it on my 96 SC400, and the car doesn't want to stay on. I checked all the cables, everything seems to be connected fine.
I wired it EXACTLY as shown here:
And used the T7-a ECU diagram:
Everything is connected like exactly as shown above. I turned the key to the ON position, initialized the system, set it to 4 Cylinders, set the throttle from 0-5V, set it Karman Sensor, and V/T OFF.
So far, the AFC turns on, there is input from the throttle, it reads the RPMs, and it can read the battery voltage.
The Problem: When I go start the car, it starts, goes to about 2000 rpm, then kind of wobbles and Stalls. Ive tried this at least 5 times messing with the cables making sure its properly connected; same thing.
The car even threw a Check Engine Light CEL: P0100 Mass Air Flow (MAF) Circuit Malfunction.
http://www.obd-codes.com/p0100
Here is a pic of the sensor check while in the ON key position but the car off:
At this point, I don't know what to do. Everything seems like its connected fine to me.
Someone please help me before I put this thing back in the box.
-David
Last edited by sc-driver; 03-27-09 at 05:59 PM. Reason: Problem Solved
02-26-09, 12:40 AM
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Hmmm. I can try that, but I am pretty sure that all 1uz-fe's used a Karman maf sensor. I researched this extensively and that's what it all pointed towards.
The 96+ SC300 are the ones with a Pressure Sensor.
The 96+ SC300 are the ones with a Pressure Sensor.
Last edited by sc-driver; 02-26-09 at 01:06 AM.
02-26-09, 01:37 AM
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Alright, I contacted him to see if he can lend a hand with this. Thanks for your help. 
Is there any possibility I may have messed up my maf sensor? I accidentally forgot to unplug the battery while wiring it up.
Is there any possibility I may have messed up my maf sensor? I accidentally forgot to unplug the battery while wiring it up.
02-26-09, 07:43 AM
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check the ECU pinout first and make sure you located your wires correctly ... but use a diagram that correctly labels the wires on the ECU ...
i've installed a dozen AFCs and i've always used a ECU diagram for the car, i've come to find out that the ECU pinout that Apexi gives you are not always correct ...
and the SC400 has a Karman sensor
good luck
i've installed a dozen AFCs and i've always used a ECU diagram for the car, i've come to find out that the ECU pinout that Apexi gives you are not always correct ...
and the SC400 has a Karman sensor
good luck
Last edited by drft_n_sc; 02-26-09 at 07:56 AM. Reason: clarification
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02-26-09, 10:17 AM
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Okay here was the deal with my NEO. I never got it to fully work, I can tell you that the Karman sensor IS NOT correct on that Pinout. I dont know where the wire goes, I just know that its NOT the correct pin. That is most likely your problem. I never got to use mine to its full performance. Also, check and make sure your settings are all a 0% Hope that helps a little. PM me again if that doesnt help and ill see what else I can think of!
02-26-09, 11:37 AM
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Okay here was the deal with my NEO. I never got it to fully work, I can tell you that the Karman sensor IS NOT correct on that Pinout. I dont know where the wire goes, I just know that its NOT the correct pin. That is most likely your problem. I never got to use mine to its full performance. Also, check and make sure your settings are all a 0% Hope that helps a little. PM me again if that doesnt help and ill see what else I can think of!
Lextreme.com says that it is pin 66 (the yellow-green wire, KS), and that's what I have.
Maybe there is a difference between wiring between 92-95 and 96+. Maybe the obdII has something to do with it?
Here is the ecu wiring diagram for the 96:
http://www.lextreme.com/lex%2096sc4001.pdf
http://www.lextreme.com/lex%2096sc4002.pdf
http://www.lextreme.com/lex%2096sc4003.pdf
All my settings were set to default. Everything was zero. The only things I changed were the # of Cylinders, Sensor Type, and Throttle Sensor. When I changed the Dec Air to 10% it was sort of able to keep it at a rough idle after I revved it a bit. Doesn't Dec Air only work on hotwire/pressure sensors?
I am going to disconnect the system and start it up later today to make sure everything is working properly.
Thank you for all your help. Much appreciated.
-David
02-26-09, 06:23 PM
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Well, I disconnected the entire system and the car started up perfectly 
.
I did come to realize that it may be the AFC that is not working properly. I changed the wiring a little bit, like this:
http://img150.imageshack.us/img150/2099/diagram2.jpg
And it actually got an input signal from the MAF sensor. But There is still no output signal from the safc. I am thinking that the neo is just not sending it through.
Here is a pic of the sensor check:
http://img27.imageshack.us/img27/6588/sensorcheck.png
As you can see, there is input from IN1, Nothing from IN2, and Nothing in OUT. I've been messing with the cables and I've concluded that the brown/white wire, the Yellow wire, and the black/white wire do not send or receive voltages.
Can there be anything else wrong? Is it possible that maybe one of the grounds is not properly grounded? That they have to be a certain distance from each other?
Help is greatly appreciated. Thank you all
.I did come to realize that it may be the AFC that is not working properly. I changed the wiring a little bit, like this:
http://img150.imageshack.us/img150/2099/diagram2.jpg
And it actually got an input signal from the MAF sensor. But There is still no output signal from the safc. I am thinking that the neo is just not sending it through.
Here is a pic of the sensor check:
http://img27.imageshack.us/img27/6588/sensorcheck.png
As you can see, there is input from IN1, Nothing from IN2, and Nothing in OUT. I've been messing with the cables and I've concluded that the brown/white wire, the Yellow wire, and the black/white wire do not send or receive voltages.
Can there be anything else wrong? Is it possible that maybe one of the grounds is not properly grounded? That they have to be a certain distance from each other?
Help is greatly appreciated. Thank you all
Last edited by sc-driver; 02-27-09 at 02:20 AM.
02-26-09, 07:08 PM
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get a diagram that tells you what wires are what on the ECU, and then from there just match them up with the wires on the AFC
if you take your MAF apart you will notice a honeycomb screen before the AIT/AF sensor ... it is a Karman sensor ... the airflow meter reads the amount of distortion that is created by the vortex generator (honeycomb screen) ... therefore you should leave the NEO on Karman sensor
if you take your MAF apart you will notice a honeycomb screen before the AIT/AF sensor ... it is a Karman sensor ... the airflow meter reads the amount of distortion that is created by the vortex generator (honeycomb screen) ... therefore you should leave the NEO on Karman sensor
02-27-09, 02:40 AM
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Updated first post with important information to all SC owners with karman sensors.
Do you know where I would be able to find such a diagram that indicates exactly where everything is coming from? All the wires were connected fine, except for pin 66.
Thanks
Thanks
Last edited by sc-driver; 03-02-09 at 11:29 AM.