175000 miles on a one owner car, no engine work ever done, 4000 mile oil changes since new, noise statrted at startup friday morning, but wife drives the car more, so noise could have been developing without my knowing. I will take it to mechanic Monday or tues, it sat 4 days before being driven,
dont know if its safe to drive, mechanic shop only 2 mile away on a 35 mph road.
its an engine noise, I have not reved it above 2000 rpm, you hear it when car is not moving, , louder with hood up, seems to be on top, and or "belt" end of engine. not a light tinny noise , not a squeal, not a fan belt noise, and not the deep rod knock noise(I have heard those decades agoon other cars).
more of a medium pitch fast rattle, turning air con on and off has little or no effect, noise will vary some come and goes on a steady RPM, , not constant will come and go. . water pump was replaced a yearand a half or more ago, all fluids are OK. alternator replaced at 120,000.
can power steering piumps make noise?
can water pumps make noise?

any way to tell if safe to drive?

 

Sounds like timing chain rattle, they loosen up when you get to higher mileage. Get a mechanics stethoscope at harbor freight for $4 and put it against the cover on the passenger side above the belts. Handy little tool

 

Here's a video of my 99 model (the 98 made the same noise) with a cold start before I replaced the timing chain tensioner.


Here's the 99 after replacing the tensoner. Can you hear the difference?

Since the 99 model has a 95 model engine, I had to replace the tensioner and the guide. But if you have a 97-99 model, only the tensioner replacement is required.

I guess the bottom line is I've replaced the tensioners on three of 4th gens to stop the morning clatter.

 

Here's a link to the thread when I replaced tensioners on a 95 and 98 model engine.

https://maxima.org/forums/4th-genera...ransplant.html

 

everything makes noise at our cars age. my timing chain was making noise at 129,000, i'm now at 290,000 and still rattling.

 

I am just curious on how the 3.0 engines are starting to do this. I am not hearing that on mines thank god. I am at 170k. I know the 3.5l are notorious for this noises.

 

thanks for the input. Noies does sound like the youtube videos.
I will update

 

Don't forget to get the gasket that was issued in the TSB. Its under $9.


https://www.nissanpartsdeal.com/part...079-31u00.html

It is not a bad job to replace the tensioner on a 97-99 model engine.

The first one that I had to replace was on 99 the I30 at roughly 225,000 miles. I paid a shop to replace that one.

So after practicing on a junk yard car, I decided to do my own on the 98 model. The homemade guide pins made the job a lot easier than it would have been otherwise.