# 1996 Nissa Altima loud noise



## gloriajt (Oct 1, 2018)

I just purchased this car for my mom and was planning on driving it 200 miles to give it to her, but it has a loud noise that I don't know whether I need to have it fixed or if it would be safe to drive like this. I am not mechanically gifted and would appreciate any feedback I can get. It is most noticeable on a cold start up and when revving the engine. https://youtu.be/d3lG_bMtFgI


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## rogoman (Dec 16, 2004)

It sounds like the noise is external, so the easiest test to do is remove both front drive belts and start the engine up listening for the noise. The short belt drives the AC compressor and it's idler pulley. The long belt drives the alternator, power steering pump, water pump and it's idler pulley. 

With both belts removed; if the noise is now gone, through the process of elimination by putting only one of the belts back on and starting the engine and listening for the noise. If the noise is there, you've found a bad component that is driven by that belt. A lot of times just spinning a pulley by hand will reveal a roughness of a worn out bearing.


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## smj999smj (Jan 1, 2006)

It sounds like the timing chain, to me. It may not necessarily need to be replaced, but it might. There are a number of issues that cause this, usually all are originally caused by debris in the oil channels restricting the flow to one or both of the tensioners. One thing you can try is removed the valve cover and you will likely see the top guide for the upper timing chain held on with two bolts. You can remove the bolts and the top guide and throw them in the trash (there was a service bulletin on this). The upper chain will slap on the top guide and make noise similar to what you have. While off, get a flashlight and try to get a look at the fixed guide on the lower timing chain. Early guides were plastic and prone to breaking and were later updated with a metal-backed guide. This, of course, requires removing the front timing cover, which is a somewhat big job if you're working on the ground. Last, if the oil channels to the tensioners are clogged with debris, it requires removal of the front timing cover, tensioners, main timing gear and oil filter. This is obviously the worst case scenario. The bolt that holds on the main gear exposes the oil channel to the upper chain tensioner when removed. Sludge will usually build-up here and needs to be cleaned out using carb cleaner or brake cleaner and compressed air. Blow into the hole behind the lower tensioner and it will blow out through the oil filter adapter. 
Sometimes an oil flushing machine will work in clearing out the channels without tearing it apart, but it's no guarantee.


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