Anybody with a 013 experience a jet engine sound with a aftermarket intake on morning start up ? We have a jcw and countryman and with the intakes installed it sounds like a jet engine at start up after sitting for awhile.goes away after a min or two. We still hear it with stock box on but more noticeable with out the box intake . Hope someone else has experienced this

 

If you're referring to the loud rushing air sound that happens on a cold start until it drops down to the normal idle (either by itself or, seemingly, by engaging reverse), I hear it on my '13 with the intake included with the JCW stage 1 kit. I don't think it lasts anywhere near minutes though.

--Matt

 

It's your turbo spinning. Free-er flowing exhaust or intake with less restrictions and larger diameter filter/piping means you will her more of the noises connected to those pipes... Nothing to worry about.

 

After I put a K&N in my 2011 S it started making that air noise, it lasts about 30 seconds. If you open the hood and put you hand in front of the intake hose you can feel the air being sucked in. When I called the dealer they told me it was normal and that it something to do with humidity.

 

my 03/2012 build cms all4 does this on a cold start while the idle speed is at 1200-1300 rpm and is most noticeable as the idle falls to the normal 700-800 rpm then it is gone

i read a post somewhere that said it was caused by the ECU adjusting the recirculation valve and wastegate to warm up the cat in the downpipe and is normal for the N18 engine

personally, i do not drive away until the idle reduces to the normal 700-800 rpm range

on a related note, i drive the last mile or 2 "easy", staying out of the boost before stopping and notice that the fan never runs after shutdown ... i figure i am allowing the turbo to cool somewhat ... i hope it improves the life of the turbo

scott

 

Most newer cars have a cold start vac air pump that scavenges air and fumes from the engine internals to prevent bad emissions or something like that. The pump runs usually for 30 seconds then shuts off. I hear the noise in my '11 and it does sound like a jet turbine, these cars makes all sorts of noises on cold start and to be honest, manufacturers try harder and harder to improve cold start emissions and improve the quickness the cats get up to temp. There are these systems that activate only during this period and it can sound alarming sometimes.

 

Ok great .yea it's about 30 seconds . I'm glad it is normal on a not normal car lol. I don't drive away In morning either till it has settled down and also leave it idle for a lil before shutting off.

 

Yup, secondary air pump. Very normal. Blows extra air (o2) down into the converter on cold starts to help feed the converter more o2 so it can convert high exhaust gas levels into safer low ones.

It's basically like blowing air into a fire to make it hotter.

It's harmless and wastes no power...

 

Minis don't have secondary air pump. Its just the high idle ar cold start. Its trying to warm the enging to normal operating temp sooner

 

Well then I stand corrected.