knocking/clicking noise under acceleration

[chrisl757]

I have a noise that is not too noisy when idling, but if I accelerate, I can definitely hear the clicking/knocking. The best way I can describe this noise is that it sounds like the old fashioned playing card that you taped to the forks on a bicycle so it would make noise when the spokes went by the card. It sounds like it is coming from the engine, and it increases in frequency as RPMs increase during acceleration.

It has been years (at least 30K miles) since it has had new plugs/wires/cap/rotor. I am planning to do this on the weekend, but I want to know if I should be aware of anything with regards to this noise.

Where do I look/listen to try to pin the source of this noise?

[Froggy69]

need to buy or find somebody that has a stethascope(sp) to use to listen with.it helps pinpoint the location of the noise a little better.
i'm kinda having the same problem with my '95. do not want to hijack so will start own thread.

[brainyass]

Change your oil and use some "valve medic or Marvel Mystery oil". It hushed my clicking noises when I used it as directed, in the gas too. If it is an irregular clicking noise, may be a worn timing chain/adjuster. Cracked exhaust manifolds, I hear, make a similar noise.

[1996Chreokee]

a cracked flex plat will make a snapping noise when you give it gas... a flex plate is found in vehicles with automatic transmissions... Its the ring gear on the torque converter for the starter

[AlohaBra]

Cracked exhaust header...on the left side...down low...by the floor board.

What year?

[chrisl757]

1996. Any way to verify it is a cracked exhaust header? And is there any quick fix to this until I can fix/replace it?

[AlohaBra]

I did a search using yahoo for:

jeep cherokee cracked header

and came up with a lot of stuff.

[1996Chreokee]

See if you can put an eyeball on it and look for any black soot... Muffler shops will usually do the inspection for free...

I have seen several break low ( toward the bottow of the engine on the drivers side) and you could identify it when the hood was open.

[citizen@large]

Originally Posted by chrisl757

1996. Any way to verify it is a cracked exhaust header? And is there any quick fix to this until I can fix/replace it?

Yep, just look all around it at the collector (near the bottom of the manifold itself just above the flange) with a nice bright flashlight. Look for sooty deposits, cracks, etc...

No quick fixes really. Unless, you get hella lucky and the only crack is in a very accessable location that can be welded while it's still on the rig...

~Good Luck

[AlohaBra]

Hey Chris....what did you find??