Knocking Noise?

[fordfarm]

I have a 1999 Expy EB w/5.4 and for past 4 years have had a clicking sound right after cold startup. Noise would go away about 60 seconds later. For ablut the past year the noise does not go away until under power on the road? Any ideas what this could be? Tappet/Rocker arm? Thanks truck runs great other than noise.

 

[Interceptor]

This sounds like the classic "piston slap" behavior for those who own 97-99 year model Ford F150 5.4L. If memory serves me correctly, this was due to pistons that were out of spec from a certain supplier. At the time, Ford dismissed concerns and said this was not something to worry about. There were those who pushed it and ended up with rebuilds and things like that. Same symptoms you describe, noise after start on cold engine from 5 - 30 seconds.

If memory serves me correctly, I also remember something about getting a oil filter which has an anti-drain back valve on it. The idea was to prevent oil from draining from the heads back to the pan.

I do not have any personal experience with the above, just what I remember when I was investigating piston slap issues with my '97 F150. Maybe someone else as more recent info.

 

[dkoenig]

I had an issue similar to this. Ended up being a loose spark plug, that once it heated up would 'tighten' up and no longer make the piston-slap noise.

 

[Thermo]

Fordfarm, take a look at your exhaust headers, specifically at the front and rear ends of the headers. Do you see a film of black dust on the block? If so, check the bolts on the headers, I bet you will find 1 or more bolts missing their nuts. This is a common problem with our motors, leading to the noises you are talking about. The fix is easy, granted it does take a little bit of time. You will need to remove the header and then extract the remainder of the bolt. Then you will need some new exhaust manifold gaskets and new bolts. Tighten down properly and go from there.