{"nhtsa_id":632210,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2002-07-11","date":"2002-03-21","document_id":"ITB02015","mfr_campaign":null,"replaces":null,"component":"ELECTRICAL SYSTEM:IGNITION:MODULE","mfr_system":null,"summary":"THIS BULLETIN IS AN AID TO THE DIAGNOSTIC PROCEDURES IN THE SERVICE MANUAL FOR DIAGNOSTIC TROUBLE CODE P1491 (VACUUM CUT VALVE BYPASS VALVE) FOR 1998 - 2002 ALL MODELS. *TT","document":null,"url":"https://open.wenmarpro.com/bulletins/632210","components":[{"id":"electrical","name":"Electrical system","parent":null},{"id":"ignition","name":"Ignition","parent":"electrical"}],"codes":["P1491"],"topics":[],"vehicles":[{"make":"INFINITI","model":"INFINITI","year_from":null,"year_to":null,"match":null,"vehicle_ids":[]}],"as_of":"2026-10-19","note":"A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.","attribution":[]}