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I know how frustrating that kind of thing can be. Is it possible that the resistor is defective? Have you checked it to confirm it functions correctly? Just a thought.
 

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why not try hooking up the temp probe to the MAF wires quickly to eliminate if it's the resistor or not?
 

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MIKEDZ said:
I Have A 97 Obd Ii Supra Recently Installed Powerhouse Street Turbo Setup With A Map Ecu. Consistently Get Mass Air Code Po100 Will Not Reset. Wiring Of Map Ecu Is Correct Can Anyone Help.
Try to setup AFM 0 to some another value. You can also use voltmeter and read the value when AFM isntaled.

Default value should be .549V but my setup is .450

This value is for anmospherical presure, if you set it too low or too high this should give you this error code.

Oh yeah i am using the tepmerature sensor form Map-ecu.
 

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The resistor has nothing to do with the code. The resistor is for the air intake temperature, the code is for the MAF signal. Two seperate things. It just so happens the two sensors, iat and maf, are contained inside the maf housing.

My best guess is either is isn't wired correctly, providing the ecu no maf signal. Or the setting in the map ecu are incorrect, i.e. you have Karmen selected instead of hotwire.

The pure voltage from the maf before any processing is 1.5~1.6V at idle if it's any help. I'd check the output signal from the map ecu at idle for a start if you are positive wiring and settings are correct. I believe the map ecu has two ground wires that need a good ground for proper operation.
 

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Discussion Starter · #12 ·
supra400hptt said:
The resistor has nothing to do with the code. The resistor is for the air intake temperature, the code is for the MAF signal. Two seperate things. It just so happens the two sensors, iat and maf, are contained inside the maf housing.

My best guess is either is isn't wired correctly, providing the ecu no maf signal. Or the setting in the map ecu are incorrect, i.e. you have Karmen selected instead of hotwire.

The pure voltage from the maf before any processing is 1.5~1.6V at idle if it's any help. I'd check the output signal from the map ecu at idle for a start if you are positive wiring and settings are correct. I believe the map ecu has two ground wires that need a good ground for proper operation.
CAN YOU EXPLAIN OR DIRECT ME TO A SITE WHEN SPEAKING ABOUT OUTPUT SIGNAL FROM MAP ECU? ALSO DOES THE TPS BROWN WIRE THAT SAYS OPTIONAL, WHICH CONNECTS TO B43 NEED TO BE CONNECTED? THANKS FOR THE INFO.
 

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My map ecu manual clearly states the tps brown wire is optional, but I would connect it. Throttle position is one of the set ups in the program.

Output signal: The maf generates a signal to tell the ecu how much air in entering the engine. It does it with a direct method of measuring through the maf sensor. The map ecu, instead of using a restrictive method like the maf, uses a pressure sensor. It reads the pressure in the manifold, then makes a calculation based on the map you loaded, then sends an airflow signal to the car's ecu just like the maf did. The map ecu is just another way to measure the amount of air going into the engine. A 0~5V signal is sent to the car's ecu so it knows how muh fuel to inject. That's about it in a nutshell. At idle, the output wire on the map ecu should approximate what the maf would be sending ~1.5V, if your fuel system is stock. I mentioned that incase you want to test the wire using a digital volt meter.

Is the car even running? Maybe list the wires you've hooked up and what you hooked them to.

Red- 12v+ ignition
Black- both go to same ground point
White- RPM
Blue- VKF/Karman Vortex Output
Green- AFM/hotwire MAF Output
Grey- VKF Input for auto-learn
Orange- AFM input for auto-learn
Yellow- O2 sensor input
Brown- Throttle Position Input
Purple and Pink (right next to red) may be different colors on different harnesses. Both are switched outputs for options.
 

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Discussion Starter · #14 ·
supra400hptt said:
My map ecu manual clearly states the tps brown wire is optional, but I would connect it. Throttle position is one of the set ups in the program.

Output signal: The maf generates a signal to tell the ecu how much air in entering the engine. It does it with a direct method of measuring through the maf sensor. The map ecu, instead of using a restrictive method like the maf, uses a pressure sensor. It reads the pressure in the manifold, then makes a calculation based on the map you loaded, then sends an airflow signal to the car's ecu just like the maf did. The map ecu is just another way to measure the amount of air going into the engine. A 0~5V signal is sent to the car's ecu so it knows how muh fuel to inject. That's about it in a nutshell. At idle, the output wire on the map ecu should approximate what the maf would be sending ~1.5V, if your fuel system is stock. I mentioned that incase you want to test the wire using a digital volt meter.

Is the car even running? Maybe list the wires you've hooked up and what you hooked them to.

Red- 12v+ ignition
Black- both go to same ground point
White- RPM
Blue- VKF/Karman Vortex Output
Green- AFM/hotwire MAF Output
Grey- VKF Input for auto-learn
Orange- AFM input for auto-learn
Yellow- O2 sensor input
Brown- Throttle Position Input
Purple and Pink (right next to red) may be different colors on different harnesses. Both are switched outputs for options.
YES THE CAR IS RUNNING. WITH CHECK ENGINE LIGHT ON. WIRES CONNECTED RED-12V+ IGNITION BOTH BLACK WIRES TO GROUND, WHITE - RPM GREEN-AFM/HOTWIRE MAF OUTPUT AND ORANGE -AFM INPUT ALL CONNECTED TO FACTORY ECU PER MY 97 SERVICE MANUAL A31 B69 B66 B58
 
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