Loud knocking noise

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Dave_66

New Member
Joined
Aug 25, 2010
Posts
2
Reaction score
0
Location
Hoffman Estates, IL
I have a 2001 EB with the 5.4. About a week ago I started getting a loud knock when I started the car and it would go away after it ran for a few seconds. Yesterday I stopped at a stop light and the truck died (first time it ever happened) When I started it back up something broke and now there is a loud knock when it is a idle or when I pushed on the gas. Once I had it at 20 or 25 the knock would go away but as soon as it slowed down it came back. There is no smoke or oil leak as well as no warning lights coming on and the oil pressure gauge is fine. Can I get some ideas on what it might be? The noise seems to be coming from the bottom of the motor so would it most likely be the crank shaft?


Thanks
 

joezek

Full Access Members
Joined
Jul 20, 2010
Posts
350
Reaction score
24
Location
psl, FL
Rod bearing knocks usually don't affect oil pressure. That could be the problem. The way I always check for a rod knock is by unplugging one spark plug at a time, if the noise doesn't go away then reconnect it and try the next cylinder. When you remove spark from the bad cylinder it will stop knocking (at idle).

If it's a rod knock then the engine needs to be torn down and major engine work done.

Is the oil full and clean? Have you checked other possibilities like various pumps that are on the engine? My A/C compressor makes some noise sometimes and it's on the bottom of the engine.
 

Maurice J Wright

New Member
Joined
Jul 19, 2020
Posts
1
Reaction score
0
Location
29412
I have a 03 5.4 expedition my engine has a hard nock and leaking oil from the bottom do any one have a clue what might be the problem
 

riphip

Full Access Members
Joined
Nov 6, 2018
Posts
641
Reaction score
189
Location
Memphis, TN.
May be broken cam follower under valve cover. Get a piece of hose to listen over the valve covers to see if coming from either head locations
 
Top