Curious About Two Things

[llll1l1ll]

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]

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.


Sent from my iPhone using Tapatalk

[johnrando]

No clutch so can't answer #1. Haven't noticed #2.

[telijah]

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]

I actually am a bat.

[az3579]

#1. My RPMs stay exactly the same.

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

Sent from my SCH-I510 using Tapatalk

[Newjack]

1. My rpms do increase ever so slightly.

2. I am not a bat.

LG Revolution + Tapatalk

[nike001]

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]

^Are we looking at the 900 rpm's at idle?

[az3579]

^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]

Ahhh....is that a video?

HTC Thunderbolt+TT

[nike001]

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]

Sorry. Only shows up as a pic on TT.

HTC Thunderbolt+TT

[az3579]

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]

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]

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]

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]

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]

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]

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]

Mine does that same thing where the rpm's will drop before returning to the normal idling rpm

[llll1l1ll]

I was thinking this morning - before I had any coffee!! - that it might be the fuel pump or a clogged filter.