Two problems related to timing tensioner have been reported for the 2006 Nissan Altima. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2006 Nissan Altima based on all problems reported for the 2006 Altima.
The motor started making noise a week or so ago. The timing chain has become loose due to faulty parts installed my Nissan. The guides for the chain break which causes the tensioners to fail and then the chain gets loose and bounces around the housing. Nissan has known about the problem and tried to hide it and should be held accountable and forced to repair their faulty work.
Abnormal engine noise has been apparent since I bought it in 2011. I especially notice it at start up and it has become increasingly harder to start on first try. Independent service shop confirmed the timing chain tensioner needs replaced.