I recently picked up an '06 MCSa and my first mod was the Alta Air Diverter. Before installing the Air Diverter, I only have 150 miles on the car and she ideld smooth. After installng the Air Diverter, I noticed a slight vibration. I could litelay see it in the steering wheel. Since it was getting dark, I had the lights on. By the time I got home it was dark out and the lights were relecting off the vehicles in front. That's when I noticed the headlights vibrating as well. These were all symptoms post install.

So my first thoughts were to go back and make sure I installed everything properly. Upon opening the hood, I noticed the rubber seal on the passenger side slid down about 2 inches. I adjusted (slid it back into position) and closed the hood. Started the engine, and found this made no difference in the vibration. After reopening the hood, I noticed the rubber seal had slid down again.So, I devided to remove all the seals and see if this stopped the vibration. It did not stop the vibration.

Then I took a closer look at the stock air diverter and noticed that it did not have the raised sides. Not only that, the thing gets HOT quickly. This conducts heat from the engine, bringing it over the intercooler. This doesn't seem very efficient to me. Now, the stock air diverter has metal screw monts and a plastic cover. This doesn't conduct nearly as much heat. My assumption is that the factory seal on the underside of the bonnet is interferring with the Alta Air Diverter "metal sides" and the rubber seals are binding against the hood tranferring the vibration from the engine, through out the car.

Now that I've discovered this, I've replaced the stock air diverter and the vibration has disappered. I chose not to remove the stock air diverter seal on the underside of the bonnet. Maybe if this is removed, the vibration will disappear. However, I'm still not conveinced this is the right mod for me. The heat transfer is a big issue for me. Doesn't make since to have heat conducting over the intercooler.

Thougts, suggestions, comments... please.

 

That's a really strange issue...

I'd contact Alta to get their point of view about this.

 

Thanks. I sent a note to Alta tech support. I'll let you know what they say...

 

Oddly enough, I believe the autos are showing that they have MORE vibration at idle, coasting, and off-idle than their manual trannied brethern... It appears there's some extra bracketry down there!

 

1. Your supposed to remove the diverter thats attached to the bonnet....
2. If you ask Alta the Diverter doesn't fit the Auto perfectly because the engine sits up higher by about 1/2".
3. I took a dremel and shaved off about 1/8" off of the diverter all the way around. Because otherwise it will eventually make a dent upward in your bonnet (I have the dent).

 

Thanks for all your responses. Actually, Adam from Alta called me and emailed me explaining that the Alta Air Diverter is not compatible with automatics. I guess I had to learn the hard way. I've gone back to the stock air diverter. :(

mdsbrain - nice work around.

 

This is a pity, since the Alta diverter is a great idea IMHO. But, since I have a manual and have removed the stock plastic diverter that attaches to the bonnet, and *still* can see clearly where the Alta rubber seals rub against the paint on the inside of the bonnet (making me feel good that I have an adequate seal), the fact that your engine sits 1/2in higher than mine, that you still have the OEM bonnet panel and the moving Alta seal attests to some strong forces at work, suggests to me there just isn't enough room for it all to fit under your bonnet.
Personally, I'd do a work around and make it fit...but as I said, I like my Alta diverter. Of course it's modified as well (!)

cheers, and good luck,

 

That sucks that it wont fit under your hood. I personally have an mcs and was thinking about purchasing the air diverter. If you don't feel like attempting a work around with yours send me a pm and i can move it up on my list of purchasing so that you don't get nailed with a part you can't use.

erik

 

Thanks for the offer to take it off my hands guys. However, Outmotoring is where I purchased it from and they have stated that they will take it as a return. So I'll have to opt for other mods in the meantime. Alta and Outmotoring have both been exceptionally helpful.