Tapping noise
Thread Starter
8th Gear
Joined: Feb 2007
Posts: 8
Likes: 0
Tapping noise
I have a loud tapping noise on cold startup. When oil temp gets to 160 it can only be heard from outside car with hood open. I have removed all rockers and pushrods. They look good and I don't see any broken springs. I used a stethescope and the tapping is loudest at the waterpump and front cover. All belts were removed and no change. I don't think it is piston slap because it lasts too long and never stops. Thanks for any advice.
Safety Car
Joined: Oct 2004
Posts: 4,816
Likes: 132
From: Plano TX
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
How many miles on the clock? I had a lifter(s) go bad on me but it wasn't till way up there in miles...270k range, replaced lifters at 274k. Mine started by tapping briefly when cold then go away quickly. The tapping time progressed as time went by till it wouldn't go away till the engine started heating up. Then all of a sudden, it became loud. Tore down the top end and replaced lifters, springs, rockers, pushrods, guides, seals and all needed gaskets of course. No more problems.
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
Might want to pull your codes in case of a misfire taking place but sort of sounds like a bad lifter...really bad. Might try doing a compression test to verify and expecially on the #1 or 2 cylinders since you are hearing it up front.
Thread Starter
8th Gear
Joined: Feb 2007
Posts: 8
Likes: 0
No codes. On cold startup when the noise is loudest at water pump. When I put the stethescope at a point where the head meets the block near the lifter area the sound is much quieter. When I first heard the noise I thought lifters. After using the stethescope I am not sure.
Le Mans Master
Joined: Jan 2009
Posts: 7,767
Likes: 19
From: East Texas
No codes. On cold startup when the noise is loudest at water pump. When I put the stethescope at a point where the head meets the block near the lifter area the sound is much quieter. When I first heard the noise I thought lifters. After using the stethescope I am not sure.
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Tech Contributor
Joined: Oct 1999
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From: Charlotte, NC (formerly Endicott, NY)
When I first started reading your post I thought piston slap but once I finished I think it isn't. Piston slap goes away once the engine is warm. Piston slap noise usually disappears once the oil temp is in the low 100s. It will be loud for quite some time if the engine is idling and warming up but as the oil temp comes up it will all of a sudden diminish in volume until it can't be heard over the space of 40 to 50 seconds.
Bill
Bill
