98 civic ex code confusion
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98 civic ex code confusion
So My car is idling like crap, getting terrible gas mileage and idling really rough and sputtering. I just had another lower mileage d16y8 swapped in so this issue is wiring related for sure I just don't know where to start. I'm getting a p0122 sensor a low circuit input. I am also getting a p1508 for an iacv malfunction. New tps sensor and calibrated to 0.50 volts with the throttle closed but when it's wide open it only reads like 4.1 volts. As far as the iacv I've cleaned it and I know it's working. I do not have the plugs mixed up either. I need some guidance as where too start so I'm not throwing money at parts I don't need. Any help is appreciated!
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Re: 98 civic ex code confusion
Run the mechanical basics first: cam and spark timing, valve adjustment, compression test.
Make sure all sensors are plugged in properly, by checking the wire colors.
TPS should read 0.4 volts closed. The wide open reading isn't very important.
Make sure all sensors are plugged in properly, by checking the wire colors.
TPS should read 0.4 volts closed. The wide open reading isn't very important.
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Re: 98 civic ex code confusion
I have done all the mechanical basics. Everything checks out there. Plugs are 100 percent in the correct place. Also cleaned the plugs and no difference. I noticed the iacv and the tps sensor are on the same little harness and both the iacv and tps are getting low voltage so it has too be wiring. Should I throw an ecu at it? I really don't know what else too do besides replace the harness. The wires for the iacv and tps look fine and aren't open anywhere
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Re: 98 civic ex code confusion
The nominal 5 volt voltage powering the sensors comes from a regulator inside the ECU. I don't know what the spec is for how low it can go.
Test the wiring by unplugging the ECU and measure resistance of the sensors from the ECU end of the wires. It should match what you measure at the sensors.
Test the wiring by unplugging the ECU and measure resistance of the sensors from the ECU end of the wires. It should match what you measure at the sensors.
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Re: 98 civic ex code confusion
The nominal 5 volt voltage powering the sensors comes from a regulator inside the ECU. I don't know what the spec is for how low it can go.
Test the wiring by unplugging the ECU and measure resistance of the sensors from the ECU end of the wires. It should match what you measure at the sensors.
Test the wiring by unplugging the ECU and measure resistance of the sensors from the ECU end of the wires. It should match what you measure at the sensors.
Just tested the pinout. At the tps sensor testing the yellow and blue wire it reads 4.9 volts. At the ecu it reads 0.03 volts. So what the hell does that mean lol. I don't have a very good grasp on wiring.
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