1999 Ford Expedition

Tiny
SNOBRDRPRO
  • MEMBER
  • 1999 FORD EXPEDITION
  • V8
  • AWD
  • AUTOMATIC
  • 13,200 MILES
In my moms ford expedition, when she starts it in the morning when its cold it has a knock for bout 10 seconds then goes away. And does not do it when its warmed up. I live in nevada so mornings are 20's and 30's. Could it be a wearing rod? Or maybe something else, thanks for the help.
Tuesday, March 31st, 2009 AT 7:39 PM

9 Replies

Tiny
JAMES W.
  • MECHANIC
  • 2,394 POSTS
If it were a rod bearing it would get worse as the engine warmed up. It could be a wrist pin in a piston, but I doubt it. Is it a "heavy" knocking sound or more of a clicking? Please advise.
Was this
answer
helpful?
Yes
No
Tuesday, March 31st, 2009 AT 9:03 PM
Tiny
SNOBRDRPRO
  • MEMBER
  • 55 POSTS
It's like tapping a screwdriver on the frame noise, and it starts about 5 seconds after it starts, and last about 10 seconds and that's it. Doesn't seem to effect engine or drivability just would like to fix it as it doesn't sound very good
Was this
answer
helpful?
Yes
No
Tuesday, March 31st, 2009 AT 9:14 PM
Tiny
JAMES W.
  • MECHANIC
  • 2,394 POSTS
At a warm idle, what does your oil pressure read?
Also, at a warm idle, if you crack the idle up and down a few times, do you hear the noise?
Are you sure it isn't anything in or on the exhaust system?
Are you sure it's not a lifter rattling until it pumps up.
Was this
answer
helpful?
Yes
No
Tuesday, March 31st, 2009 AT 10:42 PM
Tiny
SNOBRDRPRO
  • MEMBER
  • 55 POSTS
I was thinking it could be something in the head, but I don't know enough about fords to tear it down, but as for the oil pressure I will get you that info. Tomorrow
Was this
answer
helpful?
Yes
No
Tuesday, March 31st, 2009 AT 11:13 PM
Tiny
JAMES W.
  • MECHANIC
  • 2,394 POSTS
If it sounds like it's under the valve cover, it could be a weak lifter, a worn rocker arm or a broken valve spring. There's nothing in the actual "head" that will make noise.
Was this
answer
helpful?
Yes
No
Tuesday, March 31st, 2009 AT 11:30 PM
Tiny
SNOBRDRPRO
  • MEMBER
  • 55 POSTS
That's what I meant. I'm thinking it's a warn rocker or broken valve. The only way to check that is to pull the valve cover off correct?
Was this
answer
helpful?
Yes
No
Tuesday, March 31st, 2009 AT 11:48 PM
Tiny
JAMES W.
  • MECHANIC
  • 2,394 POSTS
You may have a worn rocker or broken valve "spring", but you won't find a broken valve or it would miss on that cylinder. Yes, the only way you'll know for sure is to pull the valve cover. Let me know what you find.
Was this
answer
helpful?
Yes
No
Wednesday, April 1st, 2009 AT 1:07 AM
Tiny
SNOBRDRPRO
  • MEMBER
  • 55 POSTS
Ok thank you for your help
Was this
answer
helpful?
Yes
No
Wednesday, April 1st, 2009 AT 1:16 AM
Tiny
JAMES W.
  • MECHANIC
  • 2,394 POSTS
Keep me posted.
Just an added thought. A cracked or broken piston skirt will make a clicking noise in the top of the engine. The only you can check this is to pull the oil pan and visually check each piston. It's a lot of work.
Was this
answer
helpful?
Yes
No
Wednesday, April 1st, 2009 AT 12:32 PM

Please login or register to post a reply.

Related Noise Knock Content

VIEW MORE