Weeks ago I noticed that my stock intercooler bellows were, perhaps, starting to crack. I looked into getting OEM replacements, but those were about $60 for the set. Then I found the Ultrik bellows for only $30.

They arrived today. The install was a bit of a pain because they do not flex well to allow the intercooler in like the stock ones did. While the intercooler was out I cleaned the inside film of oil with throttle body cleaner.

After it was all back in I started the car. It seemed to start rough and idled higher than normal, even for being cold. I figured that the boost leak must have bee rather bad, and that the ECU had been compensating somehow.

Driving around a bit allowed the ECU to relearn what boost feels like. Once it did, it was like adding the 15% pulley all over again. The power difference was huge.

Before attempting to atribute this to a clean intercooler, note that I have cleaned the intercooler before and the gain has never been so profound.

 

You know it seems like you had a boost leak. i mean i had one when i cleaned mine a put it back on for the first time....
course you could have been injusting throttle body cleaner.
I just used dawn and water then let it dry out after i rinsed it pretty hardcore.

 

I've taken the intercooler off many times to clean the inside, each time I replaced it carefully to ensure a good seal. In each case, the car had no troubles starting or idling; from the ingestion of throttle body cleaner or otherwise.
The results of installing the Ultrik bellows leads me to believe that there was indeed a boost leak, not from improper installation of the stock bellow from past removals, but from apparent small cracks in the stock bellow, the likes of which cannot be seen by my eyes. Oil is known to degrade rubber, and the shape of the stock bellows captures a small pool of oil, which sits for some time before being cleaned by my maintenance. Add to that the bellows are over 5.5 years old and it is reasonable to assume they had a hole...or perhaps it was merely flex in the stock bellows that altered the boost the ECU perceived and therefore altered any number of values to ensure the engine's longevity.

 

Who knows as long as your happy with the way it runs now right?

 

Aftermarkets boots can fight ya throughout the install. The skin will grow back on your knuckles in a week or so.

If your finding a decent amount of oil, consider a OCC which will drastically reduce what you have today. I check mine every 2-3 months and remove two tablespoons of oil. My IC does not require cleaning.

 

I do have an Alta catch can, I bought it more than two years ago. It is routed the more effecient way as described on some thread here. But my intercooler still gets a slight film of oil, albeit not at bad as before the can. I might need to get some new spongy material for inside it though, the bits it came with are starting to disintegrate. Any sugestions? I've heard steel wool. What about a natural sponge?

 

DId your boost go up when you replace the stock bellows and where was it before you changed it?

 

I've used Steel Wool w/ success. At home depo they sell these filters for kitchen hoods. they are comprised of a harder metal grill on the outsides and sandwiched in between them is a soft spun metal. I presently am using this stuff. I just cut round discs of both the soft and hard outer mesh and staked them inside the OCC. I also added an extension tube to the inside on the inbound side (about 2/3 down into the can) increasing the travel path of the air. I also have the M7 can which is pretty big.

I never really like the foam material - primarily thought it would not love the heat but may use it. A natural sponge is not going to be very restrictive I think. You really want the inbound air to travel throughout the can, exposed to as much material possible for the oil to stick.

The amount of oil I found the last time in my IC did not merit cleaning.

 

I don't have a boost gauge.

I'll try that stove hood filter stuff. You just gave me an excuse to go motoring, thanks

 

the hood filter stuff should last longer than steel wool - its looks like spun aluminum. Just cut circles and stack inside your OCC - using both the outside and inside stuff. Let me know what you think.

 

I stopped by Lowes and saw those filters. But they didn't have ones with spun aluminum in them. Also, there were like $10 to $15 each, and I couldn't get enough circles out of one of them to fill the can.

 

Sounds like you had some micro-cracks that open as the boots flex under boost. Common problem in turbo Audis (my automotive background) that have visually-acceptable boots and boost leak symptoms.

I noticed a similar rough-running condition upon changing the boots and cleaning the IC which I am fairly certain was due to the solvent left in the intercooler. Throttle body cleaner is a low-volatility cleaner compared to carb cleaner because it contains lubricants which are left behind after the solvent has evaporated. Carb cleaner or non-chlorinated brake cleaner would be better choices.

Its' funny - my most recent round of mods was just a few little things; tying up loose ends. I did colder plugs, IC couplers, one-ball, and a new belt. I swear the new belt was the biggest improvement of this round. I love when the little things make big differences - like when colder plugs on my S4 made significantly more power (due to much-reduced knock) and were followed by a new round of abuse and of course.... K03 death. DOH!

 

I don't recall what I paid or if I ended up buying more than one. They look like this. All I can tell you is that its a one time fix. Mine hasn't broken down or rusted. Also I just dropped one on top of another, no pushing them together. On the other hand the steel wool comes in a bag and that bag should last several years. Clearly the cheaper route and does the job.