Mongo

Thanks for the advice. I do not want to make this car a scorched paperweight and take my girlfriend's parents' place with it.

ROG100

Andy,
The extra parts you needed will be with you in the morning.
Roger

Mongo

thanks buddy! I put the knock sensors in today but I still need to solder on that replacement wiring harness.

Mongo

Car is running now, but there is a problem.

I have a huge whistling noise on this car that I cannot trace. It almost sounds like it's coming from the back of the motor but when walking around it, the sound carries all around the engine compartment. Sound occurs after revving it and gets louder as the engine decelerates to an idle. There is definitely a huge vacuum leak here somewhere, but I cannot locate it.

Does anyone have a good vacuum leak tool, or smoke tester that I could borrow to locate the source of this leak?


BTW: If anyone knows the torque specs on the 928 S4 intake in INCH-LBS let me know... Thanks!

ibkevin

... hehe, I remember my S4 intake R&R....

Just thought I'd share...

Mongo

Maybe you can tell me the torque specs then?

Bill Ball

Torque is 132 in-lbs.

Most likely a breather hose came off the oil filler neck base or the MAF boot. Try using a length of hose snaked down there to pinpoint the source of the whistle. The intake will probably have to come off. It's possible the MAF isn't fully seated in the boot, but it's more likely a hose underneath.

StratfordShark

You can check the seating of the MAF without removing intake - just look carefully from each side and verify that it's fully home.

With the MAF off you may be able to just feel for a disconnection around the MAF boot. There are Y-pieces on each side which I seem to remember are just a push fit into the boot. If you renewed your boot it should be OK but I recall finding these connections were very loose on my original which I replaced.

When you're reassembling the intake it's easy to pull off one of the vacuum lines which connect to underside of throttle body (one is a test point, one goes to splitter near rear fuel damper). Pull gently on these lines from outside to see if they are in place. I zip-tied these lines at the elbow connector and where the elbow pushes onto throttle body.

Mongo

OK. I will pull the MAF off tonight and see if the plastic fittings on the side have come loose as well as check the hoses in the area. I think we may have loosened up a hose during the positioning of the while installing the intake. I also am not too sure of the MAF but I could have sworn I got it seated right.

Mongo

UPDATE

The WHOLE F***ING THING has to come APART again. Vacuum leak under plenum.

Bill Ball

Hey, I've had to do it a couple of times too before I got it right. A pain, but after the first time, you will find you can do it very quickly. If it's just one of the breather hoses I mentioned, you'll only need to lift and support the intake while you refasten it, so you'll be able to leave everything else attached. Hope that is the case.

StratfordShark

Sorry to hear bout that Mongo, but as Bill says once the plenum is propped up you should be able to perform the reconnection without removing much else (unless it's under throttle body?).

How did you diagnose the leak? Do you know which connection is the problem?

Mongo

I had my girlfriend come out who has better ears than I do listen to it. Upon blipping the throttle the whistle will become apparent as the engine RPMs back down to idle. This is the air getting sucked into the ISV since the throttle butterfly closed. I checked all the other hoses and everything is on. The sounds is coming directly from under the mid-section of the intake manifold and above the throttle body.

Mongo

I think I just set a world record for pulling the intake off!

Barely over 2 hours from point A to point B. Sweet!!!

perrys4

Taking it apart is the easy task...