Help! Tired of throwing money at problem.
- Thread starter DRock9
- Start date
cjones
Founding Member
here are the first steps for a code 31:
let us know the results and i'll post the next steps if needed.
sorry about colors being inverted.
let us know the results and i'll post the next steps if needed.
sorry about colors being inverted.
For the ECT/ACT temp question, you can get close to knowing ECT temps if you have a mechanical water temp gauge. I usually check it at ambient temps (rediculously hot where I live) and at operating temps (if my mech water temp gauges says 190*F, I assume my ECT sensor is close to the same temp itself).
Ditto the ACT, though it's tougher since we dont have air temp gauges. I suppose you could pull the sensor after you read it and hit it with an IR thermometer. On the ACT (since I dont see it as crucial as the ECT), I just ensure it's not totally haywire like JR noted.
Ditto the ACT, though it's tougher since we dont have air temp gauges. I suppose you could pull the sensor after you read it and hit it with an IR thermometer. On the ACT (since I dont see it as crucial as the ECT), I just ensure it's not totally haywire like JR noted.
Here's my version of the code 31 test...
CODE: 31 (KOEO) - EVP circuit below minimum voltage. Vref (5 volt reference voltage supplied by the computer)
missing or broken wire or bad connection in circuit. Use a DVM to check for 5 volts on the orange/white wire. If it is missing,
look for +5 volts at the orange/white wire on the TPS or MAP sensor located on the firewall near the center of the car.
Use the black/white wire for the ground for the DVM.
With the sensor removed from the EGR and still connected, press the plunger and watch the voltage change on the
brown/lt green wire. Pull the passenger side kick panel and measure the voltage at the computer. You will need to
remove the plastic cover over the wires and probe them from the backside. A safety pin may prove very useful for
this task. Use pin 27, EVR input (brown/lt green wire) and pin 46, signal ground (black/white wire) to measure the voltage.
The orange/white wire is Vref and should always be 5 volts -/+ .25 volt. Be sure to measure Vref at the EGR sensor to rule
out any broken wires or bad connections.
CODE: 31 (KOEO) - EVP circuit below minimum voltage. Vref (5 volt reference voltage supplied by the computer)
missing or broken wire or bad connection in circuit. Use a DVM to check for 5 volts on the orange/white wire. If it is missing,
look for +5 volts at the orange/white wire on the TPS or MAP sensor located on the firewall near the center of the car.
Use the black/white wire for the ground for the DVM.
With the sensor removed from the EGR and still connected, press the plunger and watch the voltage change on the
brown/lt green wire. Pull the passenger side kick panel and measure the voltage at the computer. You will need to
remove the plastic cover over the wires and probe them from the backside. A safety pin may prove very useful for
this task. Use pin 27, EVR input (brown/lt green wire) and pin 46, signal ground (black/white wire) to measure the voltage.
The orange/white wire is Vref and should always be 5 volts -/+ .25 volt. Be sure to measure Vref at the EGR sensor to rule
out any broken wires or bad connections.
cjones
Founding Member
have you tried troubleshooting using the charts that i or jrichker posted??
BTW on my chart Pin # at the breakout box corresponds to the Pin# at the computer. so test pin#27 would be pin#27 at the computer.
BTW on my chart Pin # at the breakout box corresponds to the Pin# at the computer. so test pin#27 would be pin#27 at the computer.
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