1993 Explorer 4.0L missing...knocking

Reply Subscribe

Thread Tools

Search this Thread

Oct 15, 2004 | 07:47 AM

#16

blwilli

Thread Starter

Senior User

Joined: Oct 2004

Posts: 122

Likes: 0

uhm...yup

yeah, the more i think about it, the more discouraged I get. It is a low pitched SOLID sounding knock (not a rattle or pinging like valve tap or running too lean), which sounds louder under the engine than above it. It quiets when #2 is disconnected from the coil pack. I'll probably still be an idiot and try a few more things (like swapping an injector...cleaning the MAF, new PCV, injector cleaner...etc) but I'm pretty sure at this point that I'll just be wasting my time. Guess I'll have to tow it back with my Expy and start ripping it apart.

Last edited by blwilli; Oct 15, 2004 at 07:50 AM. Reason: forgot something....said something I shouldn't have.

Oct 15, 2004 | 02:42 PM

#17

blwilli

Thread Starter

Senior User

Joined: Oct 2004

Posts: 122

Likes: 0

new information....

just found out that Wal-Mart lub shop messed up...put in 10W-40 rather than 5W-30....could this cause a serious problem?

Oct 16, 2004 | 12:41 AM

#18

Clearcutter

New User

Joined: Jan 2003

Posts: 23

Likes: 0

From: In the North Pole

does yours knock at idle? mine idles smooth, no knock until engine is sped up. I found the crank shaft position sensor appears bad, it has rubbed up against the crank pulley until the crank pulley showed bad rub marks on it. I plan on changing this sensor on monday.

Oct 16, 2004 | 06:54 AM

#19

blwilli

Thread Starter

Senior User

Joined: Oct 2004

Posts: 122

Likes: 0

Its not the CPS. I've dealt with that enough times to know it right away. Yes, SOLID, DULL knock at idle, and at all other times (unless, of course the engine isn't running...LOL) AND there is a LOT of blow-by

Oct 16, 2004 | 11:28 AM

#20

Dialtone

Elder User

Joined: Aug 2001

Posts: 942

Likes: 0

From: South Texas

Have you entertained the possibility that a piston has broken the top off? I had one once that seperated at the second ring grove. Made lots of noise, bent both valve push rods (hollow pushrods so no bent valve stems), and had tons of engine blow-by. In my case, I was able to pull the head, drop the pan and replace only the bad piston / rod from a salvage yard engine.
In your case, you at least need to do compression check and possibly pull the valve cover for inspection. Since pulling the pan is not an option while engine is in the truck, my advise would be a rebuilt short / longblock if it goes that far.
Dialtone

Oct 16, 2004 | 11:45 AM

#21

blwilli

Thread Starter

Senior User

Joined: Oct 2004

Posts: 122

Likes: 0

yeah, see regardless of whether its a rod bearing, main bearing, or broken piston...block's gotta be replaced, and since the heads are as old as the block, may as well replace them to...point is...looking at a new engine (yeah right...will dump the Explorer and continue triving the Expy)