see NTB13-056 INTRODUCTION Nissan has determined that on some 2007 ? 2008 Altima Sedans and 2008 Altima Coupes equipped with the 2.5 liter four cylinder engines, a rattle noise may occur around the exhaust manifold heat shield during start up or at low engine speeds (approximately 1600 RPM). The symptom does not affect the operation of the engine or the vehicle. To address this issue, Nissan is conducting a Voluntary Service Campaign to replace the lower exhaust manifold heat shield. IDENTIFICATION NUMBER Nissan has assigned identification number PB053 to this campaign. This number must appear on all communications and documentation of any nature dealing with this campaign. See this bulletin for further detail.
