Canada - Engine Controls/Exhaust - Excessive Sulfur Odors
Bulletin
TSB2029
Issue Date
July 05, 2004
Title
EXCESSIVE SULPHUR DIOXIDE ODOUR
Component
ENGINE ELECTRICAL
Models
'03 - '04 4Runner (1GR-FE)
Market
Canada
Some customers may complain of excessive sulphur dioxide odour on 2003 - 2004 model year 4Runner vehicles (1GR-FE) vehicles under the following conditions:
^ Stop and go driving
^ Heavy acceleration
In order to reduce the sulphur dioxide odour, the Electronic Control Module (ECM) (SAE term: Powertrain Control Module/PCM) fuel cut control logic has been modified and a new catalyst is provided. Follow the repair procedure to reflash the ECM and replace the pipe assembly, exhaust front with catalytic converter.
NOTE:
For more complete understanding of the root cause, refer to TSB 1212 "Sulphur Odour from Exhaust" dated March 4, 2003
APPLICABLE VEHICLES:
- 2003 - 2004 model year 4Runner vehicles with the 1GR-FE engine produced BEFORE the Production Change Effective VINs shown below.
PRODUCTION CHANGE INFORMATION:
PARTS INFORMATION:
* The original part is currently used in vehicle production and is still available as a service part. The repair part should be used when the customer complains of sulphur dioxide odour.
REQUIRED SSTS:
WARRANTY INFORMATION:
ECM (PCM) IDENTIFICATION CHART:
NOTE:
2003 model year 4Runner vehicles, which have been flash reprogrammed using the procedures in this TSB, will contain upgraded 2004 model year OBD II logic. Refer to the 2004 model year 4Runner Repair Manual information on ETAS when checking Power train Diagnostic Trouble Codes (DTCs) on 2003 model year vehicles that have been reprogrammed.
ECM REPROGRAM PROCEDURE:
1. Check for the Authorized Modification Label affixed to the vehicle in the location shown in Figure 2. If there is no label present, proceed to step 2.
2. Connect the Diagnostic Tester to the vehicle and select "CURRENT ECU CAL" from the "ECU REPROGRAM MAIN MENU." To determine the vehicle's current ECM calibration, Figure 1 shown.
3. Proceed to Flash Reprogram the ECM (PCM) by following the procedures in TSB #941 titled "ECU Flash Reprogramming Process", for 2001 and late applicable models
NOTE:
Errors during the flash reprogramming process can PERMANENTLY DAMAGE the vehicles ECM (PCM). In order to minimize this risk follow the steps below:
- Make sure that the battery voltage is no less than 11.4 volts.
- Install a battery charger and set on a low setting to assure that the battery voltage DOES NOT FALL BELOW 11.4 VOLTS during the reprogramming.
- If battery's state of charge is in question, test with SST No. J-44350 "Midtronics Battery Tester".
- Confirm that the engine hood is up, parking brake is set and all accessories are OFF (i.e., audio system, A/C, interior lights, headlights, etc.)
- DO NOT perform the reprogramming process until the engine room temperature is 70°C or less.
- Confirm cable connections between the vehicle and Diagnostic Tester are secured.
- In case of Error Message "Cannot go to Reprogram Mode, "refer to TSB #0959 "ECU Flash Reprogramming Error Message."
- Do not interrupt the operation and keep all doors closed during the reprogramming process.
4. Select the proper ECM (PCM) calibration file for the model year vehicle and reprogram the ECM (PCM).
5. After completing the ECM (PCM) reprogram, the zero point calibration must be performed. Refer to TSB No. 1332 "Zero Point Calibration."
6. Start the engine and warm up the vehicle to normal operating temperatures before test-driving.
7. Test drive vehicle to confirm proper operation and to readjust the ECM (PCM) "Learned Values." Drive the vehicle using light to moderate acceleration in mostly stop and go type driving. Allow the vehicle to shift fully through all gears and at various shifter positions (D, 3, 2, 1).
8. Enter the following information on the Authorized Modification Label shown in Figure 2 using a permanent maker.
- ECM (PCM) part number.
- New ECM (PCM) calibration number.
- Your Dealer code.
- Reprogramming date.
CATALYTIC CONVERTER REPLACEMENT PROCEDURE:
1. Refer to ETAS 2003 or 2004 model year 4Runner Repair Manual:
Section: Exhaust Pipe Assembly (1GR-FE)
NOTE:
Issue of this Technical Service Bulletin is to ensure that proper repair information is available. IT DOES NOT CONSTITUTE AN AUTHORIZATION FOR REPAIR. Normal provisions of the formal warranty policy, as applicable, will apply.