haha yes I am seeing boost on the gauge, just haven't hit positive pressures on purpose, just on the FI base tune right now, and still need to break the turbo in for a few hundred KM's.

UPstream of the Check valve!!! (aka manifold side of check valve) lol

http://www.youtube.com/watch?v=BTrhtOT5Zv8


http://www.youtube.com/watch?v=2yJqMXPzpfw

So I went out and bought a Vibrant Silicon 90deg coupler for my intercooler outlet (forgot to take pictures before putting the bumper back on); and I wish I had done it sooner but... mission accomplished, everything is back in place and the car is running great so far (only put 170kms on so far). Going to get a log off to MM tonight and hopefully within the next 2 weeks I can start hitting positive manifold pressures and submit a second log. Thanks Everyone for the help this forum was amazing for all the questions I needed... I'll update the first few posts with a short summary of my build when I get some time.

Okay so on cold starts and only on cold starts I can hear a high pitched noise coming from my engine bay. It has been very hard to pin point but as I get a chance I am going to jack the car up and get someone to cold start it while I'm underneath. As for now I have reduced it down to 3 possible sources.

1) A Shitty Clutch on one of my belt Pulleys

2) I sheared the head off from the top bolt connecting the air pump hose to the GReddy downpipe so it is possible that the air is squealing through a very very small gap that is not visible.

3) Something is wrong with my turbo (Doubtful but I don't what to rule that out).

Now to explain a little more; this ONLY happens when the car is completely cold started (ie car has sat for like 8 hours). The sound lasts about 20 seconds (sound goes away before the car is even close to warmed up) and from what I have gathered I can hear something click off at the same time the sound goes away. Now I can't be certain but the sound is either the air pump clicking off or a clutch on one of my belts disengaging, I haven't been able to pinpoint it yet in the 3 days my car has been startable since the turbo install.

So a few questions are:
Has anyone experienced this before?
Does the air pump start up as soon as the car is started then shut off after 20-30 seconds of running?
Is there anything else that this sound could be coming from?

I tried to get a video but it didn't do it, must not be cold enough from driving around earlier this evening; on the contrary I was getting a weird electrical sounding "whine" when my key was switched to the on position without starting it. Seemed to be coming from the alternator... not sure if this helps back up the disengaging clutch theory or if that is normal for an alternator but I have to say I've never heard anything like that before. Here is the sound when the ignition is in the on position but not started:


http://www.youtube.com/watch?v=UEwweMRKCxo

Mine does this in the mornings when its cold. It's most likely just the air pump since you said it only did it on cold starts. Mine makes this noise for about 30 seconds or so. Just remove the system. The AP will block the CEL.


EDIT: My 8 is NA so it most likely nothing to do with the turbo or anything turbo related

The high pitched whine is most likely due to your air pump. I experienced this issue when my air pump was on it's way out. The pump only runs on a cold motor and only for approx 30 seconds to 1 minute.

methinks you are more tuned into your engine noises than you were previously ;)

sounds like normal sounds .

Okay thanks everyone... I doubt my airpump is on it's way out only 40000kms (25000mi) on the vehicle .... I may try removing the sheared off bolt from the downpipe with some vice grips and puting a new one in there to see if there is maybe a tiny space between the gasket and downpipe makine that sound.

Haha, maybe so but I have always been pretty tuned into what my engine is sounding like... rarely do I listen to music over the sound of the rotary and with such low kms on my car the sounds havent really changed at all until the turbo install.

I am also noticing at 3000rpm while holding the throttle constant I am getting a kind of chattering sound. It is either my midpipe bracket rattling on the frame(was a little bit bent to close to the frame after UPS got their hands on it) or when I put my gauges in I shifted the insulation under the radio head unit around a bit and I can just hear the tranny louder now... either way no big deal.


I had someone else warn me that this would happen because of BOV VTA but when I am cruising at over 3000rpm (happens more frequently in Higher gears and almost always in 6th) if I just push the clutch in and hold it the rpms will drop and then bounce at 800 for a bit then stall the car. I don't think this has anything to do with the BOV as I havent even boosted the car yet and when this happens it is from a low load cruise senario (ie bov should be closed)... any comments on that? Possibly from my now much more free flowing exhaust? This is really not a big deal either, just somewhat of an annoyance knowing that the odd time I may stall the car on the highway.

Edit: Oh and is that normal from the video above for an alternator to make that sound when the ignition is switched to on but the car is not running? I can't say I've noticed that before but as Brettus said I am quite a bit more tuned into listening to my engine now.

Possibly BOV related if your BOV spring is too weak it could be venting at idle . Have you tried adjusting it ?
Probably tuning related or a vac leak though .

Sorry - no definately not normal . The throttle normally makes a similar sound but at a much lower volume - which is what I thought you were talking about initially . Do the screwdriver to your ear trick and narrow down where it is coming from .
Disconnect the throttle body plug ....

^^ I am almost certain it is coming from my alternator... you can kind of tell from that video as I pull it away and get closer to the alternator it does that, I can't think of any electrical changes I did other than wiring the gauges. Used Add-a-fuses for power and ashtray light bulb wire for switching the lights of the gauges on. I'll try the screwdriver thing though...

I took your advice Brett, I bought more 1/8" line and some brass fittings to tee into my jet air hose with my wastegate signal... figured I better do that before I get a wot log off to mm when my first calibrations make it back to me. I'll tee in as close to the intake charge pipe as I can.

Wait wait wait...

I don't see any pulley movement in your last video. That high pitched whine is being caused by your throttle body. I was under the impression you were hearing the noise with the car actually running. Is this incorrect?

Disconnect the throttle body plug and retry . Mr wong and myself are pretty sure it's the throttle .

Good - it does make a difference . Although once MM has tuned for WOT you can increase boost somewhat without it affecting your tune so don't get hung up on having max boost for his logs .

Yes this is incorrect..... the car is NOT running in the video, that is with the ignition switched to ON but the car NOT started...

The other problem I am having is a high pitched sound when the car is started cold... but I am almost certain it has something to do with the air pump/hose because it is very loud and most definitely not coming from my throttlebody. Here is a video of the car COLD STARTED and the sound I am hearing for 20-40 seconds long; you can hear the buzzing (potentially from the alternator) before the car is started:

It's kinda tough to hear but you can tell when it stops near the end of the video

http://www.youtube.com/watch?v=pGMqtjvnjKw

hmm, after I watch this video, it seems like the sound is coming from the air pump up in the engine bay.... at the same time pay attention to the end of the video when you hear the sound stop (the camera is near the front right tire). Everything else seems to get louder and it could be that the sound is louder down under the car and it is too loud for my camera mic to pick up... not sure... but lemme know what you guys think.... I dont have time right now to check my throttlebody but I'll do that tomorrow morning... have a good friday fellas (or whatever it is down under right now)!

how long does it take to pull a plug out ? :o:

haha, I had an event to attend so I had to run out quickly... so you guys are saying that I should pull the plug with the car running or not running?

for the sound you are getting with the car switched to on but not started: disconnect the throttle body connector and switch the car to on and see if that sound is still there. if not, that sound is electronic throttle body. normal.

for the sound you are getting with the engine started cold: disconnect the air pump and start the car cold. if the sound isn't there, there's your answer. but im pretty sure the cold start sound is your air pump.

Alright... Thanks guys, can't wait to get my MM calibrations back now :)

Throttlebody: confirmed - after unplugging then plugging it in again the sound is not longer there.

Air Pump: confirmed - again after replugging it in the sound seems alot quieter.....weird

Thanks again guys!

Forgot to reply to this earlier.... My BOV is an SSQV so there is nothing to adjust as it is a pull type diaphram. I guess it is possible for there to be a vacuum leak but at the same time I trust my own work and was quite sure all of my couplers were sealed. I guess it could be possible that with the throttlebody closed there is more vacuum in the engine than the intake piping causing the BOV to open at these loads/engine speeds.

We'll see if MM tunes clean this up or if he catches any irregularities. Thanks!

don't hold your breath ...

Haha yeah doesn't matter anymore, snow hit yesterday and I believe it is sunk in until next spring now :(

I saw low 15's on idle vacuum isnt that low?

it's still the MM base tune...and even na at idle it was around 14.7 -15.3, thats stoichiometric

any updates?