Could my high idle be caused by...
#11
12-03-2010, 11:06 AM
Guess I'll be checking for leaks tonight when I get home. The O2 sensors appear to be functioning correctly. I only glanced at them because I replaced them for the po about 3 years ago when he bougth it. Now it is my Disco...I still think I did well for $1000...the po was just tired of the idle issue and the no support from any shops here in town.
edit: If I can't find anything...I'll have to(GULP) take it to a shop... only 4 shops in town, 2 are pos places. The other two are employing the mechanics I used to work with when I was working at the Subaru dealership in town before it closed it's doors.
edit: If I can't find anything...I'll have to(GULP) take it to a shop... only 4 shops in town, 2 are pos places. The other two are employing the mechanics I used to work with when I was working at the Subaru dealership in town before it closed it's doors.
Last edited by Chris-bob; 12-03-2010 at 11:08 AM.
#12
12-16-2010, 11:05 PM
Time to resurect this thread...
Update...I checked the intake for leaks. None. All hoses are great. Sensors all test good. So since I have a cheap scan tool that displays live data, I decided to try my friend's cheap scan tool that does live data.
Results: pending code P1314-Misfire Likely To Damage Catalyst, Bank B
(my scanner said no pending codes)
Freeze frame was all fine.
Looked at live data. HOLY COW!!! No input from MAF, HO2 sensors ALL (pre and post cat) reading 1.230-1.245 V. Coolant, air and fuel temp all good. TPS good. IACV good.
No MIL. 'S' side fuel trim at -25%
I've been looking at the Rave and will continue, but will appreciate any insight to make my job easier. Prolly MAF and something messing with the O2 sensors? I doubt the O2 sensors are bad.
Results: pending code P1314-Misfire Likely To Damage Catalyst, Bank B
(my scanner said no pending codes)
Freeze frame was all fine.
Looked at live data. HOLY COW!!! No input from MAF, HO2 sensors ALL (pre and post cat) reading 1.230-1.245 V. Coolant, air and fuel temp all good. TPS good. IACV good.
No MIL. 'S' side fuel trim at -25%
I've been looking at the Rave and will continue, but will appreciate any insight to make my job easier. Prolly MAF and something messing with the O2 sensors? I doubt the O2 sensors are bad.
#13
12-16-2010, 11:23 PM
#14
12-16-2010, 11:41 PM
#15
12-17-2010, 06:47 AM
Camel Trophy
How long has the idle problem gone on? If the MAF is dead or almost dead, the input values would only fluctuate a little. They will run with a bad MAF. Not well, but don't totally rule it out yet.. Oh, and just for the heck of it, jiggle the wiring harness to the MAF. I had a bad connector right at the MAF. You could wiggle it and idle would fluctuate.
#16
12-17-2010, 11:49 AM
How long has the idle problem gone on? If the MAF is dead or almost dead, the input values would only fluctuate a little. They will run with a bad MAF. Not well, but don't totally rule it out yet.. Oh, and just for the heck of it, jiggle the wiring harness to the MAF. I had a bad connector right at the MAF. You could wiggle it and idle would fluctuate.
#17
12-17-2010, 01:23 PM
Which O2 did you use when you replaced???
Location - just forward and aft of each cat on the exhaust down-pipe.
The following is for GEMS EFI 1996 - 1999 (early) and I copied this from a LR tech. bulletin:
The most common sensor used is zirconium based and generates a voltage of between .01 up to 1 volt based on the difference between the oxygen in the exhaust stream and that of the atmosphere.
Land Rover vehicles use a titania based sensor that operates differently. Instead of producing a voltage, the sensor changes resistance in response to oxygen in the exhaust. A rich mixture creates a low resistance in the sensor and vice versa.
A five volt reference signal is supplied to the sensor. In the case of a rich mixture, the low resistance in the sensor "pulls" the voltage low. Conversely, a lean (high oxygen content); mixture will cause the sensor to have high resistance and a high voltage. The typical range on a GEMS equipped vehicle is between less than 1 volt to more than 4 volts.
DIAGNOSIS ( in your case use a mulit meter if you dont have an OBDII scanner)
1. Attach TestBook and pull Diagnostic Trouble Codes (DTC).
2. Check the operation of the sensors using Multiple Real Time Monitoring on TestBook.
3. Start engine and set engine to about 2500 rpm for 2 or 3 minutes.
NOTE 1: When the catalytic converters start to operate as the engine warms up, the downstream sensors will not react the same as the upstream sensors if the converters are operating properly.
NOTE 2: A fixed voltage of 4.99 volts indicates an open circuit in the sensor or sensor circuit
5. Observe HO2S switching activity. The sensors should be switching rapidly between 0 volts and 5 volts Go to Oxygen Sensors/Fuel screen for a faster reading from individual sensors if necessary.
6. If the sensor is not responding, check the heater operation. The heaters are wired in upstream and downstream pairs. A bad heater will result in a lower voltage displayed in real time. Follow circuit checks below to diagnose.
7. Replace any sensor which is not switching properly.
The following is for GEMS EFI 1996 - 1999 (early) and I copied this from a LR tech. bulletin:
The most common sensor used is zirconium based and generates a voltage of between .01 up to 1 volt based on the difference between the oxygen in the exhaust stream and that of the atmosphere.
Land Rover vehicles use a titania based sensor that operates differently. Instead of producing a voltage, the sensor changes resistance in response to oxygen in the exhaust. A rich mixture creates a low resistance in the sensor and vice versa.
A five volt reference signal is supplied to the sensor. In the case of a rich mixture, the low resistance in the sensor "pulls" the voltage low. Conversely, a lean (high oxygen content); mixture will cause the sensor to have high resistance and a high voltage. The typical range on a GEMS equipped vehicle is between less than 1 volt to more than 4 volts.
DIAGNOSIS ( in your case use a mulit meter if you dont have an OBDII scanner)
1. Attach TestBook and pull Diagnostic Trouble Codes (DTC).
2. Check the operation of the sensors using Multiple Real Time Monitoring on TestBook.
3. Start engine and set engine to about 2500 rpm for 2 or 3 minutes.
NOTE 1: When the catalytic converters start to operate as the engine warms up, the downstream sensors will not react the same as the upstream sensors if the converters are operating properly.
NOTE 2: A fixed voltage of 4.99 volts indicates an open circuit in the sensor or sensor circuit
5. Observe HO2S switching activity. The sensors should be switching rapidly between 0 volts and 5 volts Go to Oxygen Sensors/Fuel screen for a faster reading from individual sensors if necessary.
6. If the sensor is not responding, check the heater operation. The heaters are wired in upstream and downstream pairs. A bad heater will result in a lower voltage displayed in real time. Follow circuit checks below to diagnose.
7. Replace any sensor which is not switching properly.
Last edited by Cosmic88; 12-17-2010 at 01:25 PM.
#18
12-17-2010, 04:42 PM
Location - just forward and aft of each cat on the exhaust down-pipe.
The following is for GEMS EFI 1996 - 1999 (early) and I copied this from a LR tech. bulletin:
The most common sensor used is zirconium based and generates a voltage of between .01 up to 1 volt based on the difference between the oxygen in the exhaust stream and that of the atmosphere.
Land Rover vehicles use a titania based sensor that operates differently. Instead of producing a voltage, the sensor changes resistance in response to oxygen in the exhaust. A rich mixture creates a low resistance in the sensor and vice versa.
A five volt reference signal is supplied to the sensor. In the case of a rich mixture, the low resistance in the sensor "pulls" the voltage low. Conversely, a lean (high oxygen content); mixture will cause the sensor to have high resistance and a high voltage. The typical range on a GEMS equipped vehicle is between less than 1 volt to more than 4 volts.
DIAGNOSIS ( in your case use a mulit meter if you dont have an OBDII scanner)
1. Attach TestBook and pull Diagnostic Trouble Codes (DTC).
2. Check the operation of the sensors using Multiple Real Time Monitoring on TestBook.
3. Start engine and set engine to about 2500 rpm for 2 or 3 minutes.
NOTE 1: When the catalytic converters start to operate as the engine warms up, the downstream sensors will not react the same as the upstream sensors if the converters are operating properly.
NOTE 2: A fixed voltage of 4.99 volts indicates an open circuit in the sensor or sensor circuit
5. Observe HO2S switching activity. The sensors should be switching rapidly between 0 volts and 5 volts Go to Oxygen Sensors/Fuel screen for a faster reading from individual sensors if necessary.
6. If the sensor is not responding, check the heater operation. The heaters are wired in upstream and downstream pairs. A bad heater will result in a lower voltage displayed in real time. Follow circuit checks below to diagnose.
7. Replace any sensor which is not switching properly.
The following is for GEMS EFI 1996 - 1999 (early) and I copied this from a LR tech. bulletin:
The most common sensor used is zirconium based and generates a voltage of between .01 up to 1 volt based on the difference between the oxygen in the exhaust stream and that of the atmosphere.
Land Rover vehicles use a titania based sensor that operates differently. Instead of producing a voltage, the sensor changes resistance in response to oxygen in the exhaust. A rich mixture creates a low resistance in the sensor and vice versa.
A five volt reference signal is supplied to the sensor. In the case of a rich mixture, the low resistance in the sensor "pulls" the voltage low. Conversely, a lean (high oxygen content); mixture will cause the sensor to have high resistance and a high voltage. The typical range on a GEMS equipped vehicle is between less than 1 volt to more than 4 volts.
DIAGNOSIS ( in your case use a mulit meter if you dont have an OBDII scanner)
1. Attach TestBook and pull Diagnostic Trouble Codes (DTC).
2. Check the operation of the sensors using Multiple Real Time Monitoring on TestBook.
3. Start engine and set engine to about 2500 rpm for 2 or 3 minutes.
NOTE 1: When the catalytic converters start to operate as the engine warms up, the downstream sensors will not react the same as the upstream sensors if the converters are operating properly.
NOTE 2: A fixed voltage of 4.99 volts indicates an open circuit in the sensor or sensor circuit
5. Observe HO2S switching activity. The sensors should be switching rapidly between 0 volts and 5 volts Go to Oxygen Sensors/Fuel screen for a faster reading from individual sensors if necessary.
6. If the sensor is not responding, check the heater operation. The heaters are wired in upstream and downstream pairs. A bad heater will result in a lower voltage displayed in real time. Follow circuit checks below to diagnose.
7. Replace any sensor which is not switching properly.
I'm goung to pull the O2 sensors this weekend to visually inspect and also test them. Hopefully it will not be raining(have to work outside since I have no garage or carport and I can't pull it into my shop at work because it's in the restricted are of an airport.)
Life really sucks sometimes...oh well.