Pulled codes from the 84" today
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Re: Pulled codes from the 84" today (flannel_man)
It may,
The fastest way to find out is to change the O2 sensor and recheck since there can be many causes depending on if you are in open loop all the time or whether its an intermittent problem. Don't forget, it's much easier to remove the sensor with the exhaust hot rather than cold.
One the other hand if you enjoy troubleshooting :p:, the following items should be checked;
Check for open in ground in ckt 413, this is the #15 (TAN) connection point on the ECM connector which should go directly to ground. If ground is OK then check the ckts 413 (which is the O2 Sensor connection to #8 pin (PURPLE) of the ECM) for a ground, it should not be grounded. If it is locate ground and repair.
You can ground the diagnostic terminal at the ALDL via paper clip between "A" and "B" terminals (top row, far right terminals) and start the car. If check engine light flashes open loop (2 and 1/2 times per second) check the items below, if the check engine light goes out for longer than 15 seconds before coming back you may have a bad ECM.
Proper Fuel Pressure: In you're case thats about 9~13 PSI,
Intake Air Leaks including AIR System operation,
Throttle Bodies Imbalance,
Exhaust Manifold Leaks ahead of sensor,
Fuel Contamination,
O2 Sensor wire grounded,
EGR not operating properly resulting in lean condition,
MAP sensor: this would only result from high vacuum which is not likely.
If above are OK, a faulty O2 is likely.
HTH
Mark
[Modified by Mark84_L383, 2:50 PM 9/27/2002]
The fastest way to find out is to change the O2 sensor and recheck since there can be many causes depending on if you are in open loop all the time or whether its an intermittent problem. Don't forget, it's much easier to remove the sensor with the exhaust hot rather than cold.
One the other hand if you enjoy troubleshooting :p:, the following items should be checked;
Check for open in ground in ckt 413, this is the #15 (TAN) connection point on the ECM connector which should go directly to ground. If ground is OK then check the ckts 413 (which is the O2 Sensor connection to #8 pin (PURPLE) of the ECM) for a ground, it should not be grounded. If it is locate ground and repair.
You can ground the diagnostic terminal at the ALDL via paper clip between "A" and "B" terminals (top row, far right terminals) and start the car. If check engine light flashes open loop (2 and 1/2 times per second) check the items below, if the check engine light goes out for longer than 15 seconds before coming back you may have a bad ECM.
Proper Fuel Pressure: In you're case thats about 9~13 PSI,
Intake Air Leaks including AIR System operation,
Throttle Bodies Imbalance,
Exhaust Manifold Leaks ahead of sensor,
Fuel Contamination,
O2 Sensor wire grounded,
EGR not operating properly resulting in lean condition,
MAP sensor: this would only result from high vacuum which is not likely.
If above are OK, a faulty O2 is likely.
HTH
Mark
[Modified by Mark84_L383, 2:50 PM 9/27/2002]
