Honda Tech Tip: Rough Idle and/or DTCs P0171, P0174 or P1171

Honda Tech Tip: Rough Idle and/or DTCs P0171, P0174 or P1171

Select Honda vehicles may experience intermittent rough idle and/or the MIL is on with DTC P0171 (Fuel Trim System Lean Bank 1), P0174 (Fuel Trim System Lean Bank 2) or P1171 (Fuel Trim System Lean During Acceleration). If normal troubleshooting procedures haven’t resolved the problem, it may be caused by a cracked intake manifold gasket(s).

Applies to: All 1998-’99 Passports; 2000 Passport – From VIN 4S6..58W..Y4400001 through VIN 4S6..58W..Y4407271.

The above vehicles may experience intermittent rough idle and/or the MIL is on with DTC P0171 (Fuel Trim System Lean Bank 1), P0174 (Fuel Trim System Lean Bank 2) or P1171 (Fuel Trim System Lean During Acceleration). If normal troubleshooting procedures haven’t resolved the problem, it may be caused by a cracked intake manifold gasket(s).

If this is the case, replace both intake manifold gaskets (P/N 8-97237-538-0).

REPAIR PROCEDURE:
Refer to page 6A-22 of the 1998, 1999 or 2000 Passport Service Manual.
1. Remove the intake manifold from the cylinder heads. Separating the upper and lower intake manifold sections is not necessary.
2. Remove both old intake manifold gaskets. Be sure to carefully remove all of the old gasket material.
3. Install the new intake manifold gaskets.
4. Reinstall the intake manifold with the new EGR valve gasket (P/N 8-97104-317-1) and the new throttle body gasket (1998-’99 models: P/N 8-94389-939-0; 2000 models: P/N 8-97193-729-1).

Technical service bulletin courtesy of Honda Parts Express.

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