Jerking at low RPM in high gears - Ford Mustang Forum
LinkBack Thread Tools
post #1 of 3 (permalink) Old 11-13-2013 Thread Starter
Dburwell's Avatar
Joined: Nov 2012
Location: Bothell
Posts: 70
Jerking at low RPM in high gears

My 2003 gt started jerking at low rpm recently (I'm not shifting too early). Its mostly in 4th and 5th, but it happens in lower gears sometimes too. It doesn't really happen when my car is fully warmed up, which is strange. The only code my car has is one for the evap system. I'm assuming its a malfunctioning purge valve that is causing the code, but I don't think that it would make my car jerk like it is, since the code has been there for some time. I just filled up today and added a can of Seafoam so hopefully that makes some sort of difference. I have no idea where to start for this and honestly I'm getting kind of sick of the constant problems with this thing. Any suggestions/experience with this kind of thing? Thanks.

Dburwell is offline  
Sponsored Links
post #2 of 3 (permalink) Old 11-14-2013
SHELBY GT 350 Member
Classic Member
4.6L Member
SoCal2V's Avatar
Joined: Sep 2010
Location: see user name
Posts: 8,705
Think they call that misfiring. Doublecheck that cel to make sure you're not getting a cylinder specific (P030x) dtc. Pull the COP's, inspect the boots for any damage or deterioration, replace as necessary. With the COP's out, look down into each of the plugwells for any moisture (coolant). If it's wet, find out why. Next, pull and inspect the plugs - if it's been a while or never then just figure on replacing them. You can get arguably the best plugs for your car, regular copper tip Autolite 764's very inexpensive, otherwise a stock replacement platinum plug is fine.

2001 GT Convertible
/1967 Coupe
All the usual bolt-on's /200 I6, C4

And a few Explorers too... 2008 4.0 XLT 4x2, 1996 XLT 5.0 4x2, 2003 Sport Trac XLT 4.0 4x4
SoCal2V is offline  
post #3 of 3 (permalink) Old 11-16-2013 Thread Starter
Dburwell's Avatar
Joined: Nov 2012
Location: Bothell
Posts: 70
My car has misfired before but it felt different than this. I'm not getting any codes for it either. I just replaced the plugs a couple months back, and everything seemed to be in working condition. I guess I'll check it out tomorrow morning and I'll give an update as soon as possible. Thanks for the input! You seem be the most helpful person on these forums.
Dburwell is offline  
Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the Ford Mustang 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:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a VALID email address for yourself, otherwise you will not receive the necessary confirmation email needed to confirm, validate and activate your new AFM member account.

Failure to provide a VALID email address, will result in the cancellation of your new AFM member account registration.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

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
Trackbacks are Off
Pingbacks are Off
Refbacks are On

For the best viewing experience please update your browser to Google Chrome

Search Engine Friendly URLs by vBSEO 3.6.1