1995 850 Turbo - Weird whistle noise?

ARMeyer27 · Post by **ARMeyer27** » 26 Mar 2015, 10:33

So i have noticed over the last week or two that i have had a strange noise. When im on the accelerator, i get a whistle'ish noise, to be honest to me it sounds like suction, like a vacuum line is just freely sucking in air, and what seems more weird to me, is it sounds like its coming from the rear of the car. It has gotten louder over the week and its starting to worry me. Once the car is up to speed and it shifts into high gear the noise seems to go away, spikes on the gas pedal result in the same sound making almost a blow off valve kind of noise. Car details below.

1995 850 Turbo Sedan
Engine codes: P0440 - EVAP Emissions System, i tried a new gas cap hoping that was it but it came back
Known Issues: Oil leaks, a lot from the oil cap that i cannot seem to get to fit right (it moves around when tight)
Miles: 175k
PCV: Done approx 6 months ago, all new system from FCP, probably not relevant but i always seem to see that being the cause of almost everything on here so i thought i would let you know its been done

Recent Work:
New brake pads and rotors on all 4 wheels - This seemed to be when the noise started, it may be coincidence im not sure. At first i thought it was the e-brake shoes wearing in with the new rotor, but the noise is getting louder so i don't think that's the case anymore. Braking feels smooth and works well.

Could this have to do with fuel pressure and tank pressure? maybe? The car runs great and if not for the noise i would not know of any problem, Turbo boosts normally (i think.. 3/4th in the white) and i havn't noticed any major power loss.

Please anyone got any ideas? I'm lost and i don't want to cause more problems by not fixing it ASAP

. Thanks in advance.

crlande · Post by **crlande** » 26 Mar 2015, 12:51

I had a whistle noise from my roof rails on '94. The paint peeled up a little and acted like a reed from a wind instrument.

ARMeyer27 · Post by **ARMeyer27** » 26 Mar 2015, 12:54

crlande wrote:I had a whistle noise from my roof rails on '94. The paint peeled up a little and acted like a reed from a wind instrument.

appreciate the reply, I'll look into that but i don't think that's the problem as my roof rails are scraped off to be all silver :\

Post by **Ozark Lee** » 26 Mar 2015, 15:12

Check your intercooler hoses. I had one that started getting noisier than the standard turbo whistle and I found that I had a hole in one of the intercooler hoses. In my case it was fairly large, about half the size of a dime, and it showed signs of wear around the hole itself so it was pretty easy to spot.

...Lee

ARMeyer27 · Post by **ARMeyer27** » 26 Mar 2015, 16:03

Ozark Lee wrote:Check your intercooler hoses. I had one that started getting noisier than the standard turbo whistle and I found that I had a hole in one of the intercooler hoses. In my case it was fairly large, about half the size of a dime, and it showed signs of wear around the hole itself so it was pretty easy to spot.

...Lee

i dont see any holes in the intercooler hoses, however i did notice there is oil seeping on top of the rubber boot that it clamps inside of (towards the front of the car) what does that mean?

also, while checking for the holes i noticed oil spatter under the air intake hose, just above the accordion part, just behind a rubber line that plugs in there.. whats that line and is this a problem?

ARMeyer27 · Post by **ARMeyer27** » 27 Mar 2015, 08:59

Ok so driving in this morning i noticed that this suction kind of noise has basically replaced the turbo noise. there used to be a defined high note to the engine now its this noise. boost still comes on strong but i cannot seem to find the source of the noise...

ARMeyer27 · Post by **ARMeyer27** » 31 Mar 2015, 11:03

Tried to make a recording of the noise. you can clearly hear the "blow off valve" kind of sound when i let off the gas near the end of the video.

please, any ideas? this is really worrying me.

ARMeyer27 · Post by **ARMeyer27** » 01 Apr 2015, 15:07

ARMeyer27 wrote:Tried to make a recording of the noise. you can clearly hear the "blow off valve" kind of sound when i let off the gas near the end of the video.

please, any ideas? this is really worrying me.

replaced the vacuum hose going from the TCV (?) to wastegate last night.. no change. I did notice on my car for some reason the red line that i think is supposed to come from the compressor is routed to the vacuum tree instead, is that wrong? how bad?

Post by **Ozark Lee** » 01 Apr 2015, 16:22

ARMeyer27 wrote:I did notice on my car for some reason the red line that i think is supposed to come from the compressor is routed to the vacuum tree instead, is that wrong? how bad?

That is correct routing.

I can't tell much from the video, I don't hear anything horrible but it still may not be correct.

...Lee

Post by **matthew1** » 01 Apr 2015, 16:35

Sounds like a boost leak of some sort. Check lines, check intercooler hoses and lastly, intercooler itself. You have to take off the splash guard to see the bottom of the intercooler, which is where mine broke (under much more than normal boost). It's plastic on its underside.