Engine - MIL ON/DTC P201A/B/Engine Runs Rough

Date: January 23, 2009

Order No.: P-B-07.61/46l

Supersedes: P-B-07.61/46k dated May 25, 2007

Group: 07





Revision History

SUBJECT:
Model 203.040/740, with Engine No. Up to and Including 271###-30-677695

Equipped with Code 491/494 (USA Engine Control Unit)

Stored Fault Code P201A/B In Engine Control Unit, Check Engine Light On Or Engine Runs Rough

If you receive customer reports in the above model vehicles of the engine running rough at idle and/or with the check engine light on while driving, this may be caused by carbon buildup on the exhaust valve stems and/or exhaust valve guide wear and leaking valve seat rings. To resolve, please proceed in the following sequence.

1. Read the engine control unit fault memory for fault code P201A/B (misfire of cylinders xxx).

2. Remove spark plugs and perform borescope inspection of all combustion chambers. Refer to WIS document AR01.00-P-0200HA.

Note:
Turn the crankshaft until the exhaust valves are fully extended so that the valve stems and valve seats can be evaluated.

3. If the valve stems are only lightly covered with carbon, continue with steps 6 through 9.

4. If the valve stems are heavily covered with carbon, continue with steps 10 through 12.

5. If the exhaust valve seat(s) are worn, continue with steps 13 and 14.

6. Install spark plugs.

7. Free up engine by revving the engine to approximately 4000 rpm and hold at this engine speed for at least 10 minutes.

8. Remove the injection valves and replace with six-hole injection valves.

9. Flash engine control unit and perform SCN coding. Note: Use latest DAS release.

10. Remove/install/replace all exhaust valve springs with part numbers indicated in parts table. Refer to WIS document AR05.30-P-3500V. Note: The exhaust valves no longer need to be replaced.

11. Install spark plugs.

12. Flash engine control unit and perform SCN coding. Note: Use latest DAS release.

13. Perform cylinder compression leakage test and compare values of the individual cylinders.

14. If the exhaust valve seats are leaking, replace the cylinder head.

Note:
Only if the cylinder compression pressure loss between cylinders exceeded 20%.

Note:
If above repair methods are not complied with, we reserve the right to debit any warranty claims.





Parts Information

Note:
The following allowable labor operations should be used when submitting a warranty claim for this repair. This information has been generated on January 23, 2009. Please refer to Netstar --> Star TekInfo --> Star Time for the most current labor time allowance.





In Case of Warranty, use the table.