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llll1l1ll
10-31-2011, 09:17 AM
Hey Mafia,

I'm curious to see if anyone else has noticed these two things in their car. They aren't problems at all. It's just the way my car works, apparently.

1) When at a light and I push the clutch to go into first to get ready to go, I noticed the RPMs go up a little. Does the car know I hit the clutch and give it extra gas or is it because the engine has less friction because it's not connected to the clutch and not rotating the transmission?

2) When I depress and hold a certain spot on the accelerator I hear a high pitched noise. I want to say it's the electronics in the drive-by-wire setup. However, could it also mean a small vacuum leak?

Like I said, I'm just seeing if anyone else has noticed anything similar.

Best,
Pete

HokieZHP
10-31-2011, 09:54 AM
EDIT: I actually am in my car now and pushed the clutch in and at idle, when I push the clutch in, my rpms DROP slightly.


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johnrando
10-31-2011, 09:56 AM
No clutch so can't answer #1. Haven't noticed #2.

telijah
11-01-2011, 07:57 AM
1: When not in gear, foot off clutch pedal, the clutch is still "engaged" to the engine, putting some weight on it, and generally will drop the RPM ever so slightly. When you press the clutch pedal, it is relieving some weight off the engine, therefore a very slight increase in RPM.

2: Likely a vacuum line, you should not be hearing electrical whining, unless like, you're a bat or a dog or something lol

llll1l1ll
11-01-2011, 09:37 AM
I actually am a bat.

az3579
11-05-2011, 04:36 AM
#1. My RPMs stay exactly the same.

#2. I get this whining. I LOVE IT.

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Newjack
11-05-2011, 04:49 AM
1. My rpms do increase ever so slightly.

2. I am not a bat.

LG Revolution + Tapatalk

nike001
11-05-2011, 10:27 AM
http://i359.photobucket.com/albums/oo37/bsktsk8ter9/th_61d31987.jpg (http://s359.photobucket.com/albums/oo37/bsktsk8ter9/?action=view&current=61d31987.mp4)

Like this? This is what mine does and I'm having a terrible time trying to figure it out..

danewilson77
11-05-2011, 10:29 AM
^Are we looking at the 900 rpm's at idle?

az3579
11-05-2011, 05:06 PM
^Are we looking at the 900 rpm's at idle?

I think he's referring to how the RPM drops to about 550 then bounces back up to about 650-700 to normal idle speed.


http://i359.photobucket.com/albums/oo37/bsktsk8ter9/th_61d31987.jpg (http://s359.photobucket.com/albums/oo37/bsktsk8ter9/?action=view&current=61d31987.mp4)

Like this? This is what mine does and I'm having a terrible time trying to figure it out..

Did you try cleaning your idle control valve?

danewilson77
11-05-2011, 05:19 PM
Ahhh....is that a video?

HTC Thunderbolt+TT

nike001
11-05-2011, 05:25 PM
I think he's referring to how the RPM drops to about 550 then bounces back up to about 650-700 to normal idle speed.



Did you try cleaning your idle control valve?

Yep. Well.. the tech at BMW did. I was standing there watching so he definitely did it. Cleaned my MAF several times as well. New spark plugs too.


Ahhh....is that a video?

HTC Thunderbolt+TT

Lol yes Dane, It is a video.

danewilson77
11-05-2011, 05:27 PM
Sorry. Only shows up as a pic on TT.

HTC Thunderbolt+TT

az3579
11-05-2011, 05:34 PM
Does the car shake a little when it bounces back up again, or is it all smooth?
If smooth, I honestly wouldn't worry about it. I think mine does it too to some extent, but it's not nearly bad enough for me to notice or remember. Will check again tomorrow.

nike001
11-05-2011, 05:46 PM
Nope, it shakes. If it didn't shake, I wouldn't worry about it either.. but it does. That's why it drives me nuts :(

jreyes19
11-05-2011, 05:49 PM
mine has a whistle but it is because i have an cold air intake
i hear a whistle is usually caused by a small hole in the lower intake boot

az3579
11-05-2011, 06:35 PM
mine has a whistle but it is because i have an cold air intake
i hear a whistle is usually caused by a small hole in the lower intake boot

Mine has always had the whistle, even after it being replaced very shortly before I bought the car.

S85FTW
11-05-2011, 06:52 PM
Looks like DISA valve symptoms, when my went the idle got so rough it felt like it was going to stall out, but then it would bounce back up

llll1l1ll
11-07-2011, 05:10 AM
My car does not shake at all when depressing the clutch. I can't see the video in this thread because I am at work.

However, I think I found the cause of the whistle. I was just snooping around my engine bay looking for oil leaks and I saw a very brittle looking, somewhat torn lower intake boot. This might also explain the occasional geriatric-like idle.

llll1l1ll
11-07-2011, 06:13 PM
http://i359.photobucket.com/albums/oo37/bsktsk8ter9/th_61d31987.jpg (http://s359.photobucket.com/albums/oo37/bsktsk8ter9/?action=view&current=61d31987.mp4)

Like this? This is what mine does and I'm having a terrible time trying to figure it out..

For the record, my car is not doing that.

HokieZHP
11-07-2011, 07:17 PM
Mine does that same thing where the rpm's will drop before returning to the normal idling rpm

llll1l1ll
11-08-2011, 04:40 AM
I was thinking this morning - before I had any coffee!! - that it might be the fuel pump or a clogged filter.