serious problems with the car
08-18-2009, 03:09 PM
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serious problems with the car i checked the codes on it today. i have no idea what would cause these
vehicle speed output circuit malfunction
mass or volume air flow circuit malfunction
MIL control circuit fault
can anyone tell me what this means?
also my fuel pressure is only running about 30 psi
vehicle speed output circuit malfunction
mass or volume air flow circuit malfunction
MIL control circuit fault
can anyone tell me what this means?
also my fuel pressure is only running about 30 psi
08-18-2009, 03:59 PM
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Sounds like you might have either a pcm failing or some problems in the wiring harness maybe a corroded connection to the pcm or something.
How is the car acting while driving or idling? For the mass air flow while it is idling unplug it and see if the idle changes or the car dies. The mil control circuit is controlled by the PCM directly there are drivers inside that tell the lamp when to turn on and off. For it to stay off the driver needs a voltage source when ever it looses that voltage source it will turns on the lamp. For fuel pressure check the voltage at the pump make sure it is getting the correct volts if its not then just work your way backwards till you ethier have the correct volts or find something wrong with the wiring.
If it is getting the correct volts then check your FPR pull the vacuum line off see if the pressure fluctuates as a last resort pull the pump check for breaks in the fuel line and or replace it.
08-18-2009, 06:30 PM
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Sounds like you might have either a pcm failing or some problems in the wiring harness maybe a corroded connection to the pcm or something.
How is the car acting while driving or idling? For the mass air flow while it is idling unplug it and see if the idle changes or the car dies. The mil control circuit is controlled by the PCM directly there are drivers inside that tell the lamp when to turn on and off. For it to stay off the driver needs a voltage source when ever it looses that voltage source it will turns on the lamp. For fuel pressure check the voltage at the pump make sure it is getting the correct volts if its not then just work your way backwards till you ethier have the correct volts or find something wrong with the wiring.
If it is getting the correct volts then check your FPR pull the vacuum line off see if the pressure fluctuates as a last resort pull the pump check for breaks in the fuel line and or replace it.
How is the car acting while driving or idling? For the mass air flow while it is idling unplug it and see if the idle changes or the car dies. The mil control circuit is controlled by the PCM directly there are drivers inside that tell the lamp when to turn on and off. For it to stay off the driver needs a voltage source when ever it looses that voltage source it will turns on the lamp. For fuel pressure check the voltage at the pump make sure it is getting the correct volts if its not then just work your way backwards till you ethier have the correct volts or find something wrong with the wiring.
If it is getting the correct volts then check your FPR pull the vacuum line off see if the pressure fluctuates as a last resort pull the pump check for breaks in the fuel line and or replace it.
08-18-2009, 06:40 PM
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Is the alt putting out good volts when this starts to happen? I would try another pcm before you start throwing money at anything else. It starts running bad prob because of the low fuel pressure.
You can get another pcm pretty cheap now days or just borrow one from a friend if you can.
You can get another pcm pretty cheap now days or just borrow one from a friend if you can.
