I replaced my DP with the Akrapovic one quite a while ago. Immediately after installing it I noticed that on a cold start the exhaust is very, very, very loud and the engine idles at around 1200rpm. After about 15 seconds the exhaust quiets down to the normal, quiet tone and the car idles at the normal 500rpm.

I ignored it at first because I thought that maybe the new DP needed breaking in tho that didn't make much sense.

The DP is installed correctly and I have no exhaust leaks that I can see or smell.

I found THIS guy who kind of had the same problem but he had an exhaust leak on an engine gasket.


Note that the car only does this when first starting and the engine is cold (under 60F).

Does anyone else have this problem? Is it something that can be corrected?

 

Did you replace the DP gasket? If not I would start there as it is cheap and easy. Then I would work your way to the exhaust manifold gasket because they are time intensive and one of those if you are in there anyway might as well replace a bunch of ****.

 

What you hear is normal operation for the n18. The engine management makes adjustments to injection, cam timing etc. during a cold start to help warm up the catalytic converter quickly for improved emissions. Since you have removed your cat it is probably more noticeable due to the increased sound level of your exhaust. Hope this helps.

 

^ +1

I'm catless on my N18...sounds beast on cold start ups....then it mellows out to practically silent =[

 

Good to know it's probably normal. That thread I found was making me worry; thinking my akra DP may be cracked somewhere.

Porthos, I didn't replace any gaskets when I swapped the DP. I didn't think it was super necessary because the car only had 15k on it and the gasket between the turbo and DP still looked new and I couldn't sense any leaks from it.

So the N14's don't do this?

And do you think there's anyway my tuner NM could get rid of this?

 

Your problem is not a problem.

 

It kind of is a problem for me. Today I was trying to leave work (film set). Crew parking was in a parking lot in the same location as set about 100' away. I had to wait in my car for about 15 minutes for camera to cut before I could start my car and drive away.

I thought I was safe, started the car, and my coworker sprinted over waving his arms. He got to me and asked me to kill the engine because they were rolling and it was all they could hear and we had been rolling over helicopter noise all day.

It's like insanely loud when it's really cold.

 

The n14 has a similar warm up strategy. However, because the n18 has double vanos as opposed to the n14 single vanos the exhaust tone is quite a bit louder due to the valve overlap. They are able to accomplish what would normally be handled by a secondary air pump with the double vanos.

 

I have a fully catles, mufflerles, 3' exhaust. I know how loud it is. Once it is warm you can't even hear it idling, as I am sure you are aware. So while it might be a personal problem, it is not an issue with the car. Talk to the tuner maybe they can de-tune it.

 

Cool, thanks for the info and welcome to the forums!

I guess I'll just have to live with it. It's only a problem in the winter so I can probably put up with it. I definitely can't remove the DP, I'd miss it too much!

 

I would have just driven off but, I am an *** hole. Mine is catless and mine really isn't that loud on start up but, I guess it depends on what exhaust you are running. Also yeah if you got 15k on your car gaskets really are not that big of a deal. I replaced mine because I had 90k on mine.

 

I took the second cat and resonator off of my 2012 S and it is also super loud on cold starts, but mellows out when it warms up s bit. It is definitely normal. It is just louder.

 

Working on any cool movies/ tv shows?