Ford Focus Forum, Ford Focus ST Forum, Ford Focus RS Forum - Reply to Topic
Ford Focus Forum
HomeContact UsAbout UsGalleryDiscussion ForumsMarketplace


Go Back   Ford Focus Forum, Ford Focus ST Forum, Ford Focus RS Forum > Ford Focus Tech Discussions > General Technical Chat > Engine starts to idle rough when brake pedal is pressed

General Technical Chat This section is for technical discussions relating to general maintenance, electrical issues, engine trouble, and recalls.

Search This Forum | Image Search | Advanced Search    
Ford Focus Tire & Wheels FocusFanatics Merchandise

Thread: Engine starts to idle rough when brake pedal is pressed Reply to Thread
Title:
  
Message:
Post Icons
You may choose an icon for your message from the following list:
 

Register Now

In order to be able to post messages on the Ford Focus Forum, Ford Focus ST Forum, Ford Focus RS Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Additional Options
Miscellaneous Options

Topic Review (Newest First)
12-30-2012 12:07 PM
Ken2327 I have the same problem with a 2011, which is barely 2 years old. I can engage the emergency brake and release the pedal and the RPM's increase to around 850 and the vibration goes away.
12-08-2012 05:19 PM
stromberg2 Can this vibration be felt when you disengage the clutch? I have a really rough vibration that comes and goes when I let up on clutch. When it's pushed in, vibes go away. Would a bad dogbone mount cause this?

Stromberg2
12-07-2012 04:13 PM
amc49 Small enough leak in PCV hose will do it with same result.

Your vacuum leak would be power booster not master cylinder. Quick way to check. Go somewhere like big parking lot at 3 in the morning and disconnect booster vacuum supply hose and plug it. Your brakes will have no power assist then so much harder to push pedal and car will not stop as quick, the reason for being in big space by yourself. If the motor at that time idles correctly then problem is the booster.

Passenger side engine mount going bad can seem to idle rough if motor beginning to shake, it will show every time you put on brake and disappear as soon as you let off. The difference is true engine roughness versus vibration felt through chassis, the two often perceived by many as the same thing................
12-07-2012 12:58 PM
elsolo Brake light wiring shorting to ground, putting a increased electrical load on the alternator, which drags down the motor.

The IAC should compensate with idle speed increase to prevent dying, if it runs rough at 800 rpm, the IAC can't fix that.

(just a wild arse guess)
12-07-2012 10:37 AM
twlott
Engine starts to idle rough when brake pedal is pressed

noticed the other day that when you are at a stop light or in drive thru that the engine starts to idle rough but once you let go of the brake it runs like it should.

I was either thinking it could be a vacuum leak from the master cylinder or it maybe a IAC. Anyone have any ideas?

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT -5. The time now is 04:50 PM.


Copyright 2002-2014 FocusFanatics.com. All Rights Reserved : Privacy Policy : Advertise Information

Focus Fanatics Ford Focus Forum offers many fun ways for you to engage with other Ford Focus Owners from across the world. Whether it be about the aftermarket performance modifications, technical how-to's, European tuned suspension or awesome fuel economy similar to the Audi S3, Ford Fusion and Acura TLX. You can find all Ford Focus and Focus ST related information here. Join our Ford Focus discussion forums and chat with local Focus enthusiasts in your area. Challenger Hellcat - Charger Hellcat