Go Back   Ford Truck Enthusiasts Forums > Newer Light Duty Trucks > 2004 - 2008 F150
Sign in using an external account
Register Forgot Password?


2004 - 2008 F150 2004, 2005, 2006, 2007 and 2008 Ford F150's with 5.4 V8, 4.6 V8 or 4.2 V6 engine
SPONSORED BY:
Click HereAdvertisement

Welcome to Ford-Trucks Forums!
Welcome to Ford-Trucks.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Ford-Trucks Forums community today!





 
Reply
 
 
 
 
LinkBack Thread Tools Search this Thread
  #1  
Old 06-21-2013, 08:06 PM
tonbis tonbis is offline
New User
 
Join Date: Jun 2013
Posts: 2
tonbis is starting off with a positive reputation.
Cool 2006 F150 Engine Shudder, low speeds with AC on

We have a 2006 F150 w/new engine, new everything but transmission and cat. converter. When driving in warm weather with the AC on and at low speeds or idle the engine will knock and want to cut out but you rev and turn off the AC and it stops. Only with AC on. We replaced fuel filter, fan throttle took to dealer and updated the software which it stopped for 3 days and started again today. Really frustrated! Could it have to do with AC compressor or low refrigerant? Please help my husband is at his wits end and I know way more than I ever cared for with truck repair! Thanks.
Reply With Quote
  #2  
Old 06-22-2013, 11:33 AM
charz charz is offline
Freshman User
 
Join Date: Aug 2012
Posts: 48
charz is starting off with a positive reputation.
Is the truck equipped with skid plates?

I had a similar issue and it turned out the skid plate under my transfer case was bent upwards and rubbing on the exhaust making it seem like it was knocking and causing excessive vibration to the cab.
Reply With Quote
  #3  
Old 06-22-2013, 12:41 PM
tonbis tonbis is offline
New User
 
Join Date: Jun 2013
Posts: 2
tonbis is starting off with a positive reputation.
But would it do that only after the truck had been running for a while and only when the AC is on? I would think with the skid plate rubbing it would do the knocking more often.
Reply With Quote
  #4  
Old 06-23-2013, 12:51 AM
charz charz is offline
Freshman User
 
Join Date: Aug 2012
Posts: 48
charz is starting off with a positive reputation.
that's what I thought as well but these motors have a fairly loopy idle.

what happened to me was it would when the idle was loopy it would intermittently make a knocking sound and when I turned on the AC it would vibrate plus it transfered the loopy idle shake to the cab.

check underneath the truck on the passenger side right under the T-Case there's a skid plate and the exhaust is very close to the skid plate, I had bent mine helping out a friend with farm work and bottoming out over a hill and ultimately I had to scrap the plate because I couldn't get it bent out right and even after going crazy with a high speed cutter it still rubbed.
Reply With Quote
  #5  
Old 06-25-2013, 08:04 AM
jp4lsu jp4lsu is offline
New User
 
Join Date: Jun 2013
Posts: 12
jp4lsu is starting off with a positive reputation.
It could be something really odd or out of the ordinary like Charz is saying.
Being a new engine and the dealer having checked it over, I wouldn't think it would be spark plugs or Coil Packs going bad.

I had a miss due to bad plugs and it would shudder and vibrate in low RPMs in OD. Changed the plugs and it is perfect.
Reply With Quote
Old 06-25-2013, 08:04 AM
 
 
 
Reply

Go Back   Ford Truck Enthusiasts Forums > Newer Light Duty Trucks > 2004 - 2008 F150

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not 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 On
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Ac problem bigredtruckmi 6.0L Power Stroke Diesel 9 08-23-2014 06:40 PM
2010 A/C issue JE917 Cooling, Heating, Ventilation & A/C 2 08-16-2010 12:22 PM
2006 4.6 scab ruff idle stalls in turns redf150scab 2004 - 2008 F150 37 05-26-2009 05:39 PM
2006 F150 Blowing AC Fuse David G 2004 - 2008 F150 0 05-27-2008 07:54 PM
04 escape a/c problem fredpet Escape & Escape Hybrid 4 08-01-2005 02:57 PM



All times are GMT -5. The time now is 10:58 AM.


Powered by vBulletin® Version 3.8.7 AC1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Advertising - Terms of Use - Privacy Statement - Jobs
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.

vbulletin Admin Backup