[hiker74]

Upon startup our 2013 2.5i Outback has a small idle vibration and increased engine noise until it settles into the lower rpm idle. Once it settles down after a minute it stops vibrating and you can hardly hear the engine (Outbacks idle much quieter than our previous Honda CRV). Is this a normal for the 2.5i boxer? This is my first Outback as well as anything with anything besides an inline or V config engine

 

[subiesailor]

I'm not familiar with the new engine in 2013 but this is common for the older 2.5. These flat engines have 4 large exhaust ports which are not joined till the exhaust comes together right under the fire wall. When flat engines are cold they are LOUD. Also due to all the emissions reduction efforts the cold engine will race with a rich fuel mixture to heat up the cats as fast as possible.

 

[upflying]

Cold start high idle and initial roughness is normal. Part of emissions algorithms to heat the catalyic converters quickly.

 

[airgas1998]

Upon startup our 2013 2.5i Outback has a small idle vibration and increased engine noise until it settles into the lower rpm idle. Once it settles down after a minute it stops vibrating and you can hardly hear the engine (Outbacks idle much quieter than our previous Honda CRV). Is this a normal for the 2.5i boxer? This is my first Outback as well as anything with anything besides an inline or V config engine

perfectly normal...the ej25 used in the 10-12' do this as well.

 

[hiker74]

I thought it was normal. Im a new Subaru owner and just figuring out the quirks

 

[paulfolio]

I thought it was normal. Im a new Subaru owner and just figuring out the quirks

Thanks for addressing this hiker74, I'm a new Subaru owner as well and was also wondering about this!

Also, thanks for everyone's input. :29:

 

[Kolenka]

With the new owners, I'm kinda surprised nobody has reported piston slap when cold.

My 2001 did that, and I haven't seen any reports of it being addressed. I haven't seen it with the 2013 either.

 

[paulfolio]

Piston slap? Please elaborate


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[foxrider68]

With the new owners, I'm kinda surprised nobody has reported piston slap when cold.

My 2001 did that, and I haven't seen any reports of it being addressed. I haven't seen it with the 2013 either.

Wasn't that something they addressed with the FB redesign?

 

[Kolenka]

Piston slap? Please elaborate

In earlier generations with the EJ25, it was fairly common to get an engine where the pistons would "slap" the cylinder wall when the engine was cold. It was mostly due to the pistons being able to wiggle a bit, but as they expanded in the heat of combustion, it worked out. It wasn't a danger to the engine, but it did make the engine even louder with the "pinging" noise.

Wasn't that something they addressed with the FB redesign?

I haven't seen piston slap in earlier Gen 4s either, which is why I'm suddenly curious. I wonder if the tolerances just got cleaned up with tweaks over the years.

 

[subiesailor]

In earlier generations with the EJ25, it was fairly common to get an engine where the pistons would "slap" the cylinder wall when the engine was cold. It was mostly due to the pistons being able to wiggle a bit, but as they expanded in the heat of combustion, it worked out. It wasn't a danger to the engine, but it did make the engine even louder with the "pinging" noise.



I haven't seen piston slap in earlier Gen 4s either, which is why I'm suddenly curious. I wonder if the tolerances just got cleaned up with tweaks over the years.

Even my 2001 with 180K on it really didn't have what some people called piston slap - I think it was a lovely term coined way back in the day.

 

[Kolenka]

Even my 2001 with 180K on it really didn't have what some people called piston slap - I think it was a lovely term coined way back in the day.

Mine did. Although I didn't try to claim that every engine had it, just that it was common.

 

[paulfolio]

In earlier generations with the EJ25, it was fairly common to get an engine where the pistons would "slap" the cylinder wall when the engine was cold. It was mostly due to the pistons being able to wiggle a bit, but as they expanded in the heat of combustion, it worked out. It wasn't a danger to the engine, but it did make the engine even louder with the "pinging" noise.

Interesting, thanks for the knowledge.

 

[pgh]

I think it is a normal characteristic of the FB motors. My Impreza 2012 does it

 

[jrabdawg]

yeah, my '13 2.5 sounds like a de havilland dash 8 turboprop in the garage for the first minute or so. I usually hit the garage door opener and then remote start the car, cause it is loud!