Modular 4.6L Tech For all your 1996-2005+ 2V, 3V, and 4V modular motor needs.

Diagnosing engine knocks...

Thread Tools
 
Search this Thread
 
  #1  
Old 12-22-2005 | 04:10 PM
caballo's Avatar
Thread Starter
|
Exceptional Member
Joined: May 2005
Posts: 530
From: NE CO
Default Diagnosing engine knocks...

You guys probably remember my engine problem that arose a short time ago. If not here's the cliff notes

spark plug ejects.
no start condition w/ various codes.
replace fuel pump
will not idle
fuel injector wide open.
trip to ford dealer-knock appears. 200.oo bill and no progress.
replace injectors, replace cop's, replace fuel pressure regulator.

NOW car idles and drives but there is a knock.

1) any tips/tricks (oil additives that might make it go away)

or

2) any advice on how to diagnose the knock ie. main vs rod bearing or maybe valvetrain...

Thanks again...
 
  #2  
Old 12-22-2005 | 05:51 PM
caballo's Avatar
Thread Starter
|
Exceptional Member
Joined: May 2005
Posts: 530
From: NE CO
Default

Then again it might be "piston slap"... any suggestions greatly appreciated...
 
  #3  
Old 12-22-2005 | 06:00 PM
MattJ's Avatar
Senior Member
Joined: Dec 2004
Posts: 10,237
Default

is it constant or inconsistant knock? if not when does it do it? you need to explain the situation when it happens..
 
  #4  
Old 12-22-2005 | 06:19 PM
whitethunder46's Avatar
Always Detailin'
Joined: Oct 2005
Posts: 3,556
From: Dayton, OH
Default

would runing higher octane or getting is looked at with an SCT XCal do anything?
 
  #5  
Old 12-23-2005 | 11:13 AM
caballo's Avatar
Thread Starter
|
Exceptional Member
Joined: May 2005
Posts: 530
From: NE CO
Default

Originally Posted by MattJ
is it constant or inconsistant knock? if not when does it do it? you need to explain the situation when it happens..
Sorry... It's like a rod or main bearing knock(I'm guessing). it's constant and not too loud. I hear it all the time. at idle it's noticeable but not annoying. Then as I accelerate, it gets faster and a little louder...

driveability isn't effected other than the noise but I know there's a good chance I'm damaging the bottom end...(main or rod journal)
 
  #6  
Old 12-23-2005 | 11:15 AM
MattJ's Avatar
Senior Member
Joined: Dec 2004
Posts: 10,237
Default

timing chain may be hitting. that is a known problem. sounds like that could be along the lines of your problem.
 
  #7  
Old 12-23-2005 | 02:03 PM
caballo's Avatar
Thread Starter
|
Exceptional Member
Joined: May 2005
Posts: 530
From: NE CO
Default

Originally Posted by MattJ
timing chain may be hitting. that is a known problem. sounds like that could be along the lines of your problem.
You sure?! I've got a 2000 GT. I would have bet it to be rod/main bearing or maybe piston slap or valvetrain (very iffy)

Here's a refresher on what originally happened...
 
  #8  
Old 12-25-2005 | 03:55 PM
caballo's Avatar
Thread Starter
|
Exceptional Member
Joined: May 2005
Posts: 530
From: NE CO
Default

Bump......
 
  #9  
Old 12-27-2005 | 09:57 AM
caballo's Avatar
Thread Starter
|
Exceptional Member
Joined: May 2005
Posts: 530
From: NE CO
Default

So I unplugged each spark plug (one at a time) while the engine was running and the sound didn't change. Then I put a piece of pcv(no hose available) up to my ear and went up and down both valve covers and didn't notice a change in volume.

So I'm thinkin' maybe it's a valvetrain or timing chain thing...

Any thoughts?!

Should I take off the valve covers and inspect "da train" or....????
 
  #10  
Old 12-28-2005 | 10:18 AM
caballo's Avatar
Thread Starter
|
Exceptional Member
Joined: May 2005
Posts: 530
From: NE CO
Default

Okay, this is what I think originally happened when the spark plug/C.O.P. got ejected. When that happened it obviously killed the electrode on the plug, then the COP shorted out either when it hit the fuel rail or when it was bouncing around from all the cylinder air flow coming out the plug hole. When that happened it shorted out the fuel pressure regulator and the fuel pump and the other COP's and the injectors. (how, I don't know) From the repeated cranking of the engine in the attempt to restart it, I got fuel contamination in my oil. What I thought was a rod/main bearing issue seems to be a valvetrain or timing chain issue.

The reason why I think this is I changed the oil and added Lucas OIL treatment and the noise is considerably quieter AND sometime it's gone. I'm thinking it's a semi-collapsed lifter(follower). and the high viscosity oil treatment has helped to pump it back up...


thoughts?
 
  #11  
Old 12-28-2005 | 02:07 PM
caballo's Avatar
Thread Starter
|
Exceptional Member
Joined: May 2005
Posts: 530
From: NE CO
Default

de ja bump
 
  #12  
Old 12-29-2005 | 05:04 PM
caballo's Avatar
Thread Starter
|
Exceptional Member
Joined: May 2005
Posts: 530
From: NE CO
Default

Originally Posted by MattJ
timing chain may be hitting. that is a known problem. sounds like that could be along the lines of your problem.
What's the fix? replacement or mod?
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
00blkstanggt
General Tech Forum
4
06-19-2009 10:55 AM
StreetRacer
The Lounge
0
07-17-2007 09:17 PM
NoKturnaL
Modular 4.6L Tech
25
01-02-2005 06:44 PM
04GTMikey
Modular 4.6L Tech
5
12-14-2004 06:44 PM
JIM88
Modular 4.6L Tech
0
12-12-2004 09:16 AM




All times are GMT -7. The time now is 01:04 AM.