2010 Sentra piston slap?

[Stelth]

My wife drives a 2010 Sentra 2.0S. It's a nice little car, but when you start it cold, it almost sounds like a diesel. It quiets down after about 5 minutes of driving, and doesn't make that sound until the next cold start. In fact, at idle when it's warm, I almost can't hear it running.

Does that sound like piston slap? Does it mean anything?

 

[mclasser]

What kind of oil & filter are you running? Some oil filters can cause start up ticks/knocks.

 

[Ramblejam]

How much oil are you using (consumption)?

 

[Stelth]

Not using any oil.

Last OC was Chevron Supreme 5w30, OCOD. Current fill is RP 5w30 RP, RP filter.

 

[Klutch9]

It could just be injectors. Many modern vehicles have noisy injectors that can be mistaken for piston slap or valve noise, especially when cold.

 

[crazyoildude]

mileage?
how does your oil filter mount on that engine?

 

[andyd]

Yah It maybe a bad anti drain back valve in the filter. I would try a new oil filter of a different brand.

 

[artificialist]

You can buy an automotive stethoscope for a few dollars and probe different parts of the car with it to determine a cause. There are youtube videos that explain how to use it.

 

[Jeffs2006EvoIX]

I wouldn't be surprised if it was the filter too. Try an oem filter and see if it does the same thing. That noise went away in previous hyundais I had as long as I used oem filters. Weird I know.

Jeff

 

[bigjl]

Why would a different filter or different anti drain back valve cause an engine noise that lasts 5 minutes?

A few seconds delay in the hydraulic tappets/lifters is one thing but 5 minutes.

Subarus have been known to suffer piston slap but it has had no obvious ill effect in engines affected.

Injector noise is an interesting theory.

I assume when cold more fuel will be injected in much the same way as a choke on a carb.

That would certainly fit with what the op is hearing.

Perhaps some fuel injector cleaner may help.

I would be inclined not to worry too much if the car otherwise runs well.

 

[shDK]

Coult also be a leak in the exhaust manifold. A Crack or blown gasket. That close when the engine is getting warm.

 

[Stelth]

Here's a video of a guy with a 2011 Sentra with the same sound. Skip to about 3:00, that's when you can really start hearing it.

 

[Stelth]

Anybody look at the video?