Knock, Knock. Who's there? Your cylinder head. Oh, that's not a funny joke.

[MustangChris]

Alrighty ladies and gents.... the mustang is in bad shape.

SO... our custom made power steering cooler mount pierced a hole in my front-mount and the water just drains out as fast as you can pour it in... That's obviously an easy fix (1 day...)

BUT here's the BIG problem. Passenger side cylinder head *knocks* ... this isnt the "tick" this is defiantly a knock. It gets faster with RPMs, it goes away at certain RPMs, is impossible to hear at idle, and is louder on the bottom of the head opposed to the top of the head.

any ideas? We are going to crack 'er open soon, I just want to try and get a few ideas of what to look out for....

My thoughts: Lack of proper cooling caused the intake valve to heat up and either the valve and/or seat got fugged.

My uncle says he doubts that as the car isnt acting like a valve isnt seating properly. (No consistent backfires in the exhaust, no strange and unpredictable idle, no strange wide-band readings)

Anyone with more motor experience than me want to chime in? I opened the valve covers when the engine was out and everything looked great. The cams didnt even have wear tracks yet.

Additionally:
Pulled all 8 plugs. all looked fantastic. Slight brownish color on the center electrode and slight white color on the side electrode. All smelled like fresh e85. That means its getting fuel, the plugs are working fine (nothings hitting the electrodes, no signs of running lean/rich).

Also, I unplugged that coil and injector and the sound stayed exactly the same.

SO, I obviously don't think its in the combustion chamber.

Back to the head:

here's the only pic I've got from dropping in the engine....

 

[CC'S95GT]

Your motor has too many damn cams to diagnose over the internet. remove 3 and get back to us. LOL.

Do a compression ck on all cylinders. If any are out of spec then do a cylinder leak down ck.
That will tell you where the issue lies if it's in the vlvs or rings.
The knock might also be in the timing chains/ tensioners. Pull the cover and verify.

 

[the.greg]

Did you do the evenflow headcooling mod?

 

[MustangChris]

i did, but wrong side of the engine. lol. that critter lives on the D/S, this is the P/S head.

and ill do a compression test and leak down once we get it back to my apartment. I'm also sending the TB/plenum combo off to acuufab for re-work to see if that cures the idle problem

 

[the.greg]

Yeah sorry I have no ideas, after you mentioned possibly heat related I wondered about the evenflow mod lol. Hopefully its something simple, let us know! I'll do some googling and see if I can find any more ideas.

 

[MustangChris]

eh. dont work up a sweat. lol.

just curious if anyone was like "oh, dude. dont worry its just your flux capicitor.. happened to me too! $8.00 fix." kinda thing.

I have a feeling a valve follower is fugged up for some reason.

 

[RichV]

I would probably look at your lifters 1st. If you have one not pumping up or erraticaly. Do you have a cylinder narrowed down?

A knock isn't good tho. Hope it's not the bottom end. How's oil pressure?

 

[justinschmidt1]

2v ftw

 

[greenscobie86]

Oh that happened to me too. It was a flux capacitor, a simple $8 fix and I was good to go!!!



















































J/k.

Sometimes the pass. side header flange likes to make a knocking/ticking noise, a loose set of manifold bolts will make a seemingly knocking sound as well. Can you post a video of this knock?

 

[vermilion]

Remove valve cover. I hope its not a rod bearing or valve


Sent by smoke signals

 

[MustangChris]

Yea... im going to crack her open this week.... also im 99% sure its not an exhaust flange/gasket problem. . .. i can litterally feel the knock in the screw driver when i put it on the lower valve cover bolt, but not when i put it on the header...

Honed it down to cyl #4....... ug ... we dont think its a rod because it comes and goes....

 

[MustangChris]

if its a rod, at least thats pulling the motor and a few days work. pulling a head totally blows....

 

[Marvin97]

I can sympathize with you Chris, mine is about to go through the build it is because it started making a similar noise about 2 months ago. Sounds kind of like a knock but not very loud, isn't there at idle, is quiet enough I couldn't pick it up with my camera, is definitely coming from the passenger side, doesn't seem to effect performance at all. I'm hoping I can find it when I tear it down in the coming weeks, i'm more afraid that i'll get it disassembled and won't be able to find the problem.

 

[D3VST8R96GT]

Suck bro hope it all works out

The D3V

 

[vermilion]

Think about the 4 valve and lash adjusters. Hopefully its just a minor adjustment. Hell even a cracked lash adjuster isn't as bad as pulling the head off.


Sent by smoke signals

 

[MustangChris]

got a write up on that? ;-)

 

[JeremyAlan]

Chris, your car has a 03/04 Cobra motor in it correct?

 

[MustangChris]

Yes....

 

[JeremyAlan]

after re-reading your original post i agree it may be a valve problem.

but just some nasty-food-for-thought. My car had a knock much like what you are describing and it was a piston that had heated up and expanded into the cylinder wall. the knock would only be present during certain rpm sometimes. Also, when you say you think its a connecting rod, are you suggesting it may be bent?

 

[BigBore96]

Try unplugging the COP for that cylinder and see if the noise goes away.