Hello Again Folks,

Based on the information below, where should we start looking?

My mechanic and I have made significant improvements to the 2004 Discovery II with 111,000 miles. However, it is idling rough and is throwing the dreaded p1884 code.

Here is what has been replaced so far:
- ECM rebuilt
- Replaced the cam shaft sensor
- Replaced the crank case position sensor
- Coolant temp sensor
- Replaced all 4 O2 sensors
- New purge valve (Hyundai)
- New MAF Sensor (Bosch)
- New plugs
- New air filter

It drives fine off the idle circuit. Based on this information, where should we look for issues? Top 2 or 3 places to get started would be greatly appreciated.

Thanks for the help!

-Burwell, New Orleans

 

Even those of us that work on these all the time don't necessarily memorize all the codes, good idea to google and post the LR code explanation. This thread is relevant: https://landroverforums.com/forum/di...4-60026/page2/

Do you have any other codes?

If the codes don't tell you where the miss is, you need to troubleshoot using other diagnostic info. Get a ELM327 bluetooth and the torque app, make sure the oxygen sensors are cycling correctly. Make sure the MAF sensor is behaving correctly. Does the temp sensor readings correlate with expectations - you can verify with IR sensor gun (5 for pen on ebay). I would recommend unplugging the MAF and see if it improves. Unplug the oxygen sensors and see if it improves. Unplug a mid size vacuum line and see if it improves. Open the hood at night in the dark and see if there any sparks.

 

P1884 is not a relevant engine performance fault. It is a transmission code AllData reads:

BOSCH GS8.87 TRANSMISSION MANAGEMENT
P1705
P1841
P1842
P1843
and
P1884

are all System Interfaces Codes.


There is a TSB referencing the fault, but it is also transmission related and not pertaining to any kind of rough run condition



A/T - ZF TRANSMISSION/MULTIPLE SHIFT CONCERNS
No: 44/01/02/NAS
Ref:
Issue: 1
Date: 08/16/02

ZF Transmission Troubleshooting

AFFECTED VEHICLE RANGE:

Range Rover (LP) Prior to MY 2001 Discovery Series II (LT) Prior to MY 2001 Discovery Series I (LJ) Defender (LD)

SITUATION:

VARIOUS SYMPTOMS INDICATE TRANSMISSION FAULTS

A transmission complaint which follows known patterns can permit a very straightforward diagnosis provided that a logical process is followed. The purpose of this bulletin is to streamline the procedures followed by Retailers for specific complaints in the following vehicle ranges:

^ Discovery Series II and Range Rover vehicles prior to 2001 MY - Slipping on acceleration, erratic upshifts, vehicle "jerks" while accelerating, engine revs "flare" on upshifts, Fault reference #1 (page 2)

^ All Discovery (Series I and Series II), Classic, Defender and Range Rover vehicles prior to 2001 MY - Loss of drive/slipping Fault reference's # 2, # 3, # 4

^ All Discovery Series II, Range Rover 4.0 & 4.6 - Fault code P0734 (Bosch), 43 (GEMS) Fault reference # 5

^ Discovery Series II, Range Rover 4.0 & 4.6 to 1999 - Fault codes P0501, P1884 and P0722 Fault reference # 6

RESOLUTION:

ENHANCE RETAILER DIAGNOSTIC ABILITY

Following the procedures in this TIB, the Retailer will be able to quickly diagnose the above faults and understand the remedial action required. In such cases the Retailer can expedite the repair without having to gain prior authorization. Land Rover continues to require the Retailer to complete the ATER.

The ATER must be faxed to the Land Rover ZF Technical HelpLine in all cases along with details of fault codes where applicable from Testbook.

PARTS INFORMATION:

Refer to Parts Catalogs/Microcat

WARRANTY CLAIMS:

Normal warranty policy and procedures apply.
Material allowance is included in labor operation.

REPAIR PROCEDURE

INVESTIGATE DISCOVERY SERIES II AND RANGE ROVER PRIOR TO MY 2001:
SHIFT PERFORMANCE TROUBLESHOOTING - FAULT REFERENCE # 1

1. Determine the validity of the customer complaint:

^ Slipping on 2-3, 3-4 shift or 4-3, 3-2 shift

^ Engine races or "neutrals out" on 2-3, 3-4 shift or 4-3, 3-2 shift

^ Harsh shift or "jerk" on 2-3 or 3-4 shift

^ Transmission slipping on kick-down

NOTE:
Customers may also describe a double shift or a jerk/delayed shift when accelerating or that the car seems to "neutral out" or downshift to first when accelerating. These symptoms suggest an internal failure within the transmission. If an internal failure exists the fault will be repeatable in nature and WILL NOT be intermittent. Should the customer describe an intermittent problem or the dealer is unable to reproduce the customer complaint please contact the Land Rover ZF HelpLine for further assistance.

CAUTION:
Oil levels must be checked COLD with engine running. Refer to the following documents for additional guidance.

^ Oil level setting Service Alert SA00GI15 issued on 8/10/00

^ Oil level setting Bulletin 44/01/99/NAS (NO dipstick)

^ Oil level setting Bulletin 44/01/98/NAS (WITH dipstick)

2. Fault reference #1: If transmission slips on 2-3 or 3-4 shift (or both), and/or slips when a kick-down shift (or "passing gear" is called for) 4-3 or 3-2 is tried, check oil level and record results on ATER.

NOTE:
It is possible that no fault codes have been logged even though the slip may be severe (although a downshift over-speed fault code may be logged).

3. Test vehicle to verify complaint and to ensure problem is repeatable as follows:

^ If complaint relates to the 3-4 shift for example, drive the car in position D3 and confirm shifts 1-2, 2-3 are OK

^ Stop the vehicle and accelerate from rest in position D3

^ At 40-50 mph shift lever into position D

^ If engine revs increase or "flares" as the shift to 4th is made on a repeatable basis the fault is internal to the transmission

4. If the oil level is correct (or fault persists after oil level correction) AND the fault is repeatable in nature replace transmission and flush oil cooler lines.

5. Ensure ATER is completed, record fault reference # 1 on ATER and fax to HelpLine.

INVESTIGATE ALL VEHICLES PRIOR TO MY2001:

LOSS OF DRIVE OR SLIPPING - FAULT REFERENCE # 2 & # 3 & # 4

1. Determine the validity of the customer complaint:

^ Loss of forward drive

^ Loss of drive, forward and reverse

^ Loss of drive forward and reverse as car warms up

^ Slipping in drive

^ Slipping in drive and reverse

NOTE:
The loss of forward drive symptoms suggest that the "A" clutch (main forward clutch) has failed. This clutch is not used in reverse. As a result reverse gear engages and operates as normal.

CAUTION:
Oil levels must be checked COLD with engine running. Refer to TIBs 44/01/99/NAS and 44/01/98/NAS as well as Service Alert SA0015GI-15 for additional guidance.

2. Fault reference #2: If loss of all forward drive is encountered but reverse gear operates correctly perform the following:

^ Verify correct oil level. If the transmission oil level is set/filled incorrectly (too low) or if oil is lost as in the case of a severe leak from the transmission or cooler/cooler lines this fault may result.

^ On electronic transmissions the stall speed monitoring fault should be recorded in the transmission fault memory (P0722, Bosch, 27 GEMS).

^ It is possible that the oil looks or smells burnt.

3. If the fault is still present after checking/correction of oil level AND the fault occurs every time acceleration from rest is attempted, replace transmission and flush oil cooler lines.

4. Ensure ATER is completed, record fault reference # 2 on ATER and fax to the HelpLine along with TestBook fault code print outs detailing fault codes recorded.

NOTE:
The loss of drive in positions "D", "D3" or "D2" failure symptoms suggest that the first speed freewheel has failed. This can occur if "D" is engaged while the car is rolling backwards causing overload of the freewheel and subsequent failure. Transfer box chain slip can also cause this fault by providing shock loads to the transmission. In positions "D", "D3" & "D2" the freewheel holds the torque when accelerating from rest. In position "D1"the freewheel is supported by engagement of a clutch (to provide engine braking). This will "lock" the freewheel even if it has failed, allowing the car to pull away normally.

CAUTION:
Oil levels must be checked COLD with engine running. Refer to TIBs 44/01/99/NAS and 44/01/98/NAS as well as Service Alert SA0015GI-15 for additional guidance.

5. Fault reference #3: If loss of drive in positions "D", "D3" or D2" is determined but the vehicle drives when in "D1" or when reverse gears engaged, perform the following:

^ On electronic transmissions the stall speed monitoring fault code should be recorded in the fault memory (P0722, Bosch, 27 GEMS).

^ The oil may look clean and smell normal with this fault.

^ Check oil level and record results on ATER.

6. If the fault is still present after checking/correction of oil level AND the fault occurs every time acceleration from rest is attempted, replace transmission and flush oil cooler lines.

7. Ensure ATER is completed, record fault reference # 3 on ATER and fax to the HelpLine along with TestBook fault code print outs detailing fault codes recorded.

NOTE:
The symptoms of no drive in forward or reverse indicate a serious internal transmission failure BUT could also be a failure of a component outside of the transmission, for example transfer box failure. Where an internal transmission failure exists there should be a stall speed monitoring fault code stored (electronic transmissions only).

CAUTION:
Oil levels must be checked COLD with engine running. Refer to TIBs 44/01/99/NAS and 44/01/98/NAS as well as Service Alert SA0015GI-15 for additional guidance.

8. Fault reference # 4: If vehicle has no drive at all forward or reverse, check the oil level and record results on ATER.

^ If the transmission has just been fitted to the car as a result of a transmission replacement or engine repairs, the oil pump drive dogs may have been broken off during installation. Contact the HelpLine for assistance.

^ If the transmission has just been serviced, oil changed or the oil and filter changed, verify oil level and ensure that the filter and O-ring are installed correctly. Contact the HelpLine for assistance.

^ If the transmission controller DOES NOT have the stall speed fault code logged (P0722 - Bosch 27 GEMS), the failure may not be the transmission. Contact the HelpLine for assistance.

9. If the fault is still present after checking and correction of oil level AND the fault occurs every time acceleration from rest is attempted AND the stall speed fault code is logged (P0722 - Bosch, 27 GEMS), replace transmission and flush oil cooler lines.

10. Ensure ATER is completed, record fault reference # 4 on ATER and fax to the HelpLine along with TestBook fault code print outs detailing fault codes recorded.

INVESTIGATE DISCOVERY II, RANGE ROVER 4.0 & 4.6:

FAULT CODE P0734 (BOSCH), 43 (GEMS) FAULT REFERENCE #5

NOTE:
This fault code indicates that the diagnostics saw a difference between the transmission input speed and the transmission output speed that exceeded the permissible 4th gear ratio. This could be a result of actual slip or an incorrect input/output speed signal. The output speed signal is read from the auto transmission output speed sensor in the transmission. The input speed signal is a theoretical value (there is no input speed sensor in the auto transmission) calculated from the engine torque/speed signals from the EMS.

CAUTION:
Oil levels must be checked COLD with engine running. Refer to TIBs 44/01/99/NAS and 44/01/98/NAS as well as Service Alert SA0015GI-15 for additional guidance.

1. If the transmission has been serviced recently, investigate the oil level. Incorrect levels can lead to this fault code being logged.

2. Check the condition of the transmission oil for evidence of water contamination.

3. Inspect fluid to determine if it is black/burnt.

4. Determine if the oil smells burnt.

5. If there is any doubt about the oil condition, remove the oil pan and inspect and call the HelpLine for further assistance.

6. If there are no obvious signs of transmission slip or malfunction, road test the car to confirm that the transmission operates as expected.

NOTE:
There may be engine fault codes logged as well as this transmission fault code. Typically the codes are P0171, P0174. Correcting the cause of these faults will prevent further occurrences of the transmission code. However, it has also become clear that a mass air flow meter can provoke this transmission code without recording any engine fault codes. Follow LR diagnosis procedure for Mass air flow meter.

7. If all of the following conditions exist:

^ The oil level is correct

^ The oil condition was found to be normal

^ The transmission operated correctly on road test

investigate engine mass air flow meter for faults. DO NOT REPLACE TRANSMISSION

8. Ensure ATER is completed, record fault reference # 5 on ATER and fax to HelpLine at along with TestBook fault code print outs detailing fault codes recorded.

INVESTIGATE DISCOVERY II, RANGE ROVER 4.0 & 4.6 TO 1999:

FAULT CODES P0501, P1884 AND P0722 FAULT REFERENCE #6

NOTE:
The customer will probably report that the fault occurred after starting the car from cold and could also report that the car has no power, is running rough or misfiring. With the fault codes cleared the car should run fine. This fault can occur if the driver engages drive and applies throttle immediately after start up. This can lead to the stall speed diagnostics being "tripped" as the engine speed exceeds the upper diagnostic threshold. The software for the stall speed diagnostics has been altered from 00MY to prevent these codes from being recorded in error.

1. Determine which of the following symptoms exist:

^ Vehicle runs rough and has no power

^ Transmission fault lights/message displayed

^ Fault codes P0501 (in Bosch controller) AND P0722 & P1884 in transmission controller are set

^ When the fault codes are cleared car appears to operate normally

^ Customer states that the fault occurs only after starting from cold

CAUTION:
These codes can be caused by other issues and logged separately. In such cases contact the HelpLine for further assistance.

2. Confirm that all three fault codes are recorded:

^ P0501 in engine controller

^ P0722 and P1884 (V3 road speed invalid) in transmission controller

3. Clear the fault codes from both controllers and test drive the vehicle.

4. If further faults are noted during road test or fault codes are re-logged, contact the HelpLine for further assistance.

5. Use TestBook/T4 to verify the Land Rover part number of the transmission controller (ECU).

NOTE:
TestBook/T4 displays the part numbers before fault codes are accessed.

^ Old level software: Series II UHC100240/UHC100360

^ Old level software: Range Rover UHC100220

^ New level software: Series II UHC000010 or UHC00080

^ New level software: Range Rover UHC100340

CAUTION:
Series II transmission ECU's can be plugged in without any further work required. Range Rover transmission ECU's need to have the tune selected (4.0 or 4.6) using TestBook.

6. If all three codes were present AND the car operated correctly after clearing the codes AND the transmission controller ECU contains the OLD level software, install the latest level transmission control ECU with new software. DO NOT REPLACE TRANSMISSION.

7. Ensure ATER is completed, record fault reference # 6 on ATER and fax to HelpLine at along with TestBook fault code print outs detailing fault codes recorded.

 

Thanks. I checked with my mechanic and P1884 is the only code it it throwing. I had about 12 codes before and replaced several sensors, but the codes stayed. So, we determined the ECM was bad and sent it off for repair. The company that repaired the ECM confirmed the main chip was corroded and had to replaced. Once the ECM was rebuilt and replaced in the vehicle, all the codes were reset and only P1884 came back.

I have an iLand diagnostic tool and I will get it over to the Rover and see what it reads. I will also clear the accommodations.

 

Thanks! I will pass this along to my mechanic.