...or it feels that way. My 328i may have just spoiled me but I do remember FC's being a good bit quicker than my 1991 N/A feels. I decided yesterday it was because I'm simply not using all 8000rpm...so today I did a couple of redline runs in first and second and came to the conclusion that I need a shorter set of gears.

Anyway, though, point behind my writing is that after about 5~6k the car didn't have much power...and after 7k it still climbed but the rate at which it did was just shy of falling on it's face. Power should be PEAKING at 7k!

It's my assumption that my sleeves are seized, and the VDI may not be functioning properly. With my last cars...all S4's...cleaning the sleeves was an easy thing because it never failed that I was taking the intake assembly off for some reason or another...so I just slipped them (sometimes dragged kicking and creaming or broken) out and cleaned them thoroughly, by hand. I'm wondering if anyone's had any success getting them to free up IN the car? I'd like to avoid pulling the intake...even though I would like to replace all my vacuum fittings and de-emission the car...

The VDI barrel I can get to and clean by hand, I believe, without any real issue.

Also, I'm wanting to confirm my belief. If I tell the missus to plant her foot on the gas while I watch the actuators...there is a rev limiter on the S5's, right? Or just a buzzer? And the actuators will still "actuate" with the car in neutral, at a stand still, right? Either way I doubt over-revving the engine for just an instant will cause any real problems.

Thanks!

 

I think you have to have load to open the 5/6 actuators on the S5, so you really cannot do it at idle. Also the S4 5/6 ports activate by exhaust pressure, but the S5 activate by vacuum. You can pull the hose off the diaphram and try to activate by vacuum to verify if they will rotate.

I used a method of putting a glob of grease on the actuator linkage. Then took the car for a spin, hit redline a couple of times. I came back and found that the glob of grease had been moved, indicating that the linkage had rotated the 5/6 port actuators. Kinda crappy, but it worked.

Good Luck!

 

Actually, the S5 is actuated by air pressure from the air pump, not vacuum, so you have to use compressed air. I do highly advise you not to, because it only takes around 2 psi to open them and over pressurizing them will bust the internal diaphrams. Just put a blob of grease on the "stop" and see if it gets tranfered to the lever after a few WOT runs. By "stop", I mean the little piece of metal that keeps the lever from rotating past a certain point.

Do the grease method before trying compressed air. Opening them with compressed air is for when you know they aren't opening and you need to verify they aren't stuck.

 

Yeah I'm going to confirm that they're moving. It's hard to do the grease thing becuase of the oil leak the car had, and the previous owner's driving it in it's condition, has coated the entire engine bay with sludge. Makes it a less dirty job to not have to reach in there and feel around lol.

Biggest question is...is there a way to clean the sleeves up in the engine?

 

I just read that if the actuators are removed you can slide the sleeves out without tearing down the intake assembly. Can someone confirm this?

Thanks!

 

No, you can't remove the aux sleeves without removing the intake manifold. When you remove the actuators, all you can get out are the actuator rods - which is not recommended because it can be hard to line them back up with the sleeves. First, you need to verify if they are opening or not. Since you have an s5 its easy because you can rev it in neutral while looking in the engine bay and see if they move, same for the VDI.

If they are stuck, you can try removing the actuators and rotating the actuator rods by hand. Unfortunately theres no good way of getting anything on the actual sleeves since they are sealed inside the manifold to prevent vacuum leaks.

Also, there is a rev limiter - its around 8500 RPM.

 

Sorry for the bad info, I should look before I leap, especially trusting my memory.
Yeah, my bad. I haven't messed with the 5/6 ports in 5 years. I remembered that I ultimately used my Mity Vac to test them. I must have used pressure side.

FSM says .85-1.4 psi.

 

alright...sleeves are NOT rotating. So I guess it's time to tear down. That'll be my project either this weekend or next...