Cold start up popping noise

[sweetfrs]

I got it alittle yesterday and then this morning it was reallly loud pop sound idk wtf it is but i know its normal. My cars gonna be at toyota overnight tonight so they can duplicate the sound, we'll see wht happens

[Maverick22]

Keep us posted

[Muskokan]

-22 thismorning and this was worse than ever... Hope it's normal cause it does it a lot.

[Mikem53]

Originally Posted by Muskokan

-22 thismorning and this was worse than ever... Hope it's normal cause it does it a lot.

At least it started for you... That's crazy cold..
It was 23 degrees here this morning.. So it's probably 55 in the garage
And it will pop and stumble some when I go to start it.. My car is spoiled down here in the Carolina's... Stay warm!

[smbstyle]

Mine is not as nearly pronounced as the video above, but only during the first 20 seconds or so on start up there's a very very faint pop sound, then once the revs drop down it goes away, and doesn't happen at any other point in time. Sounds like it's just running very rich on startup.

[Muskokan]

mine went on for a good minute thismorning, very loud and the first time ive seen it actually change the rpms.

weather is just starting to stay cold here now, im goign to get a video in the morning and bring it in to subaru. it does look like this is common... hopefully this car doesnt explode in the cold. to broke for a beater.

[Luckrider]

Originally Posted by whtchocla7e

I, too, have experienced the popping sounds at startup during the cold winter months.

I posted a thread about this exact issue earlier and your video is what I experienced this morning. I hope this isn't a common occurance with this factory cold start tune.

[Rayme]

I heard that noise all last winter during cold starts, warm weather came back and made it through the entire summer and never heard it again.

It has yet to be cold enough here for me to hear it again so far this season...so it sounds like normal crazy cold start sound this car makes in the cold. The exhaust is crazy loud during the startup, the cam phasing / spark timing must be acting up to warm up that cat fast and makes wierd ass noise in the process.

[Young_makaveli]

Originally Posted by Weeber

Hey guys,

So a fair bit of owners on an Australian forum seem to be disheartened due to a "champagne cork" like popping in the engine bay during first start up and only during cold starts.

One claims the engine rev's drop before popping also noise seems to be apparent on both transmission types.

This to me, sounds like the initial stages of the infamous DI seal problem folks seem to be having. I don't know if I am being paranoid but better safe than sorry.

So my question is, would this be something they (and I, who do not have such issues) should be worrying about?

Thanks!

I can confirm that the revs drop under 1k before any popping occurs

Imo this is normal on cold starts

[kuhlka]

Originally Posted by Young_makaveli

I can confirm that the revs drop under 1k before any popping occurs

Imo this is normal on cold starts

My popping/missing/stutter sound as in the video only occurs during the first 15-30 seconds of startup. Once the revs drop to 1k and lower it goes away completely. It only started doing it once the temps dropped below 40F.

If I start the car and immediately change gear out of park (auto trans), the revs immediately drop to ~1k and there is no weird popping. I assume it's the crappy cat warm-up procedure with negative timing. Maybe the engineers in Japan didn't spend much time testing in freezing cold environments?

[Young_makaveli]

Originally Posted by kuhlka

My popping/missing/stutter sound as in the video only occurs during the first 15-30 seconds of startup. Once the revs drop to 1k and lower it goes away completely. It only started doing it once the temps dropped below 40F.

If I start the car and immediately change gear out of park (auto trans), the revs immediately drop to ~1k and there is no weird popping. I assume it's the crappy cat warm-up procedure with negative timing. Maybe the engineers in Japan didn't spend much time testing in freezing cold environments?

I don't know if this matters or not but my car is manual so maybe that goes into account ?

As soon as a drive the car for 15 mins, the noise would disappear

[kuhlka]

Originally Posted by Young_makaveli

I don't know if this matters or not but my car is manual so maybe that goes into account ?

As soon as a drive the car for 15 mins, the noise would disappear

After 15min of driving, the car should be fully warmed up.

Have you noticed if the pop/stutter goes away once you get rolling? I can bump to neutral in my auto and it goes away completely as the revs drop immediately as it passes through reverse. If you give a light blip of throttle does that make a difference?

It'd be nice to know what exactly is causing the pop. Seems almost like a misfire/cutout or split second power loss like cylinders not firing intermittently. The fact that it goes away as soon as the revs drop and the car warms up makes me think it's a startup fueling issue that Subaru or Toyota should sort out.

[FRSFirestorm]

Mine does this when left outside and 25 F or lower. It's a backfire in the intake system. Cold fuel in the intake not atomizing and probably pooling. Cold start enrichment (the choke for old carburated guys). This fuel is then ignited in the intake system and you hear the muffled pop.

[Snowball]

I'm getting the same popping noise on cold starts as well...was kinda alarming at first, but after the car settles down all is well.

yesterday was -7 degrees celsius (approx 19 F) car starts at 2k idle...then 1.5...then 1. About 4 minutes later, the car is ready