Go Back   F150online Forums > Powertrain & Mechanical > V8 Engines
Sign in using an external account
Register Forgot Password?


Reply
 
 
 
 
Thread Tools Search this Thread Display Modes
  #1  
Old 04-05-2009, 06:50 PM
Member
 
Join Date: Jul 2008
Location: Anchorage, Ak
Vehicle: 2002 Ford F250
Posts: 59
My take on the infamous knocking noise at idle & pinging under loads...

I'm hoping I may be correct on my year long search for the fix of the knocking noise at idle, which almost sounds like a quiet deeper sounding rod knock. And also the pinging problems alot of people have been having.

I believe they are caused by the same problem...

Caked carbon & oil on the pistons, walls and valves.
Everyone knows that carbon build up will cause pinging due to the extra compression in the cylinders but is anyone aware that this oil/carbon build up will cause knocking noise at idle??? (sounds very similar to rod knock at idle but has a little deeper tone also may be refered to diesel noise) Especially noticeable when pulled up to a drive thru or next to any building.
The knock also does not go away when engine is warm.

I personally used a mirror to look into the bottom of my intake manifold and found something that shocked me... a pool of oil from none other then the PCV system. This is even with a new PCV. So I know oil vapor is getting into the cylinders and most likely caking up.

Did alot of searching and finally stumbled on some information of the caked oil causing engines to sound almost exactly like rod knock at idle but just a little deeper sounding. I believe the explanation was something about a shockwave making the noise just like pinging does.

My plan of action is do the throttle body, TB elbow, & intake manifold cleaning followed by a decarbon procedure with seafoam. And probably some BG44 in the gas tank. Hopefully and finally making an oil trap so this doesn't happen all over again.

Has anyone else had this combo. of problems?
And am I on track with my thoughts on this caked oil problem causing rod knock noise during idle?
Reply With Quote
Old 04-05-2009, 06:50 PM


 
 
 
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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 Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off


All times are GMT -4. The time now is 12:01 AM.





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
 
Contact Us Advertising Privacy Statement Terms of Service Jobs Forum Text Archives
Emails & Contact Details