Can oil on plugs cause knocking?

ALCobra2001

New Member
Sep 28, 2020
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Blue Bell
Hello.
I have a 2001 Cobra that started stalling, then a bad knocking sound.

I figured it was the typical bad head/ valve tick.

When I had it inspected my mechanic thought it sounded like a rod bearing so I stopped driving it.
I've been trying to find the source.

I thought it was from the driver's side.
I pulled the fuel injector connectors one at a time, knocking seemed to move.

Checked for loose plugs and that's when I found oil in the passenger side plug wells.

Noise also seemed to come from that front side.
It's quiet when starting, knocks when warm.

Oil pressure gauge doesn't change, normal.

I was ready to get rid of the car, so you think oil on plugs could cause knock?

Thanks for your time.
 
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HemiRick

I'd be looking at jacking under the house
Jun 28, 2020
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Memphis TN
No oil on plug will cause a miss/smoking but not a knock....A rod knock is easy to identify if an experienced mechanic siad thats what the noise is believe him
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
36,799
12,726
224
Massachusetts
Might be a couple rods knocking.

Post a video, with a few easy revs and let off the gas. Pretty easy to identify rod knock.
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
36,799
12,726
224
Massachusetts
Pull your plugs and coil packs, clean the oil off and reinstall. Usually if the coil is an issue, it generates a misfire code on that cylinder. Sometimes moving the coil around to get the problem to move around can be a good way to troubleshoot.
 

ALCobra2001

New Member
Sep 28, 2020
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Blue Bell
Thanks, I'll try it.

I'm paranoid of trying to remove the plugs, they break easy, right?

I just need to take a shorter video so I can upload it.

Like I said, I was sure cylinder 7 or 8 had either the bad valve problem or bad rod bearing.
While pushing on the coil pack the knock went away.
Then the knock sounded like front of passenger side.

Thanks again.
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
36,799
12,726
224
Massachusetts
Keep it simple for now. Take the coil packs off 7 and 8 and move them to the opposite side of the engine. See if the problem follows. Leave the plugs alone for now
 

BigFatRoss

Member
Oct 18, 2020
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Chicago land
Just another idea, take a long (16 inch or longer) screw driver, or if you don’t have one you can use a wooden doll rod or broom stick handle. Use the stick as a stethoscope, place the rod up to your ear and put the other end where you think the noise is coming from. I would think if you have the car jacked up and running, and place the rod on or near your oil pan you should definitely hear a rod knock if in fact that is what it is.
 

ALCobra2001

New Member
Sep 28, 2020
5
0
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57
Blue Bell
Hey, that's a good idea, to check under the motor.

I tried doing that from the top but it's hard to pinpoint the location.

I have videos, but they're too large to attach, even ten second ones.