You are correct. I skipped over that one because I didn't think that the TSB title: 'OBD II misfire monitor' applied to your problem.
18-31-97 superseded to 18-22-98.
[background=transparent]NO: 18-22-98[/background]
[background=transparent]GROUP: Vehicle Performance[/background]
[background=transparent]DATE: Jun. 12, 1998[/background]
[background=transparent]SUBJECT:[/background]
[background=transparent] Misfire Monitor[/background]
[background=transparent]THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 18-31-97, WITH EFFECTIVE DATE OF JAN. 30, 1998 WHICH SHOULD BE REMOVED FROM YOUR FILES AND NOTED IN THE 1997 TECHNICAL SERVICE BULLETIN MANUAL (PUBLICATION NO. 81-699-98004). THE DECARBONIZING PROCEDURE HAS BEEN REVISED ALONG WITH THE LABOR OPERATION TIME ALLOWANCE. ALL REVISIONS ARE HIGHLIGHTED WITH **ASTERISKS**.[/background]
[background=transparent]MODELS:[/background]
1997 - 1998 (TJ) Wrangler
1996 - 1998 (XJ) Cherokee
1996 - 1998 (ZJ) Grand Cherokee
NOTE :THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH THE 4.0L ENGINE.
[background=transparent]SYMPTOM/CONDITION:[/background]
[background=transparent]Malfunction Indicator Lamp (MIL) illuminated with either a Multiple Misfire or individual Cylinder (1-6) Misfire Diagnostic Trouble Code (DTC) recorded in the Powenrain Control Module's (PCM) memory. The MIL illumination may be accompanied by engine vibration.[/background]
[background=transparent]DIAGNOSIS:[/background]
[background=transparent]Refer to the 1998 2.5L/4.0L/5.2L/5.9L SF1 Jeep[/background]
[background=transparent] Diagnostic Procedures Manual (Publication No. 81-699-97019), test TC-106A for the Multiple Cylinder Misfire DTC or test TC-107A for the Cylinder # (1-6) Misfire DTC. For any future reference, record and document Freeze Frame data.[/background]
NOTE :BOTH TEST TC-106A AND TC-107A ARE REVISED WITH TECHNICAL SERVICE BULLETIN 26-12-97 RELEASED DECEMBER 1997. DO NOT USE THE PROCEDURE LISTED IN THE DIAGNOSTIC PROCEDURE MANUAL UNLESS THE REVISED PAGES HAVE BEEN INSERTED.
[background=transparent]Perform the repair procedure identified in the Powertrain Diagnostic Procedures Manual unless your diagnosis identifies that an engine mechanical problem could be causing the OBD II Misfire DTC. If the Powertrain Diagnostic Procedures Manual identifies a possible engine mechanical problem, perform the Repair Procedure.[/background]
[background=transparent]Here is the repair procedure.[/background]
[background=transparent]1. Operate the vehicle until the vehicle reaches operating temperature.
2. Remove the air tube from the throttle body.
3. With the engine at an idle, spray the entire contents of Mopar Combustion Cleaner, p/n 04318001, directly into the throttle body. Allow the vehicle to load up with the cleaner to the point of almost stalling out.
4. Shut the engine OFF after the entire can is ingested.
5. With the hood closed and the vehicle parked inside the garage, allow the vehicle to soak for two to three hours. This will ensure that the engine will maintain its temperature and will allow proper solvent penetration.
6. **Drive the vehicle to fully warm up the engine.
7. If the vehicle is equipped with an automatic, place the gear selector into L, if the vehicle is equipped with a manual, place the transmission into first gear.
8. On a suitable road that will allow the vehicle to be driven safely at the posted speed limit, accelerate the vehicle until the engine reaches 4500 rpm.
9. Hold the engine speed at this rpm for 15 seconds.
10. Slow down and pull to the side of the road, then allow the engine to idle for five seconds.
11. Repeat Steps 7 through 10 two more times.**
12. With the vehicle at operating temperature and within the freeze frame data recorded for the diagnostic test, verify that the misfire condition has been corrected. [/background]
[background=transparent][background=transparent][background=transparent] [/background][/background][/background]
