Hi all, I have a 2001 4.6L f150. My truck has developed an issue where on a cold start it will tick and clack intermitently. While the truck warms up idling, it will make the noise then eventually go away then come back going from quiet to progressively louder till the truck reaches normal operating temp on the gauge. At first I thought this could be a loud lifter, but would it not be loud even when the engine is warm? I think its safe to rule out a oil pressure issue as the noise stops completely when the truck reaches its normal temp. Then it sounds great. You can put a stop watch every time as to when the noise will go away. I had put sea foam in the oil with no success, did the old ATF fluid trick in the oil, no Success, Did the diesel fuel in the oil before a change, no success. If it was a lifter you would of thought it would of cleaned itself up. Any Ideas? Like I said only clacks on cold start up till it reaches its normal temp. Any sensors that would cause this issue? Thanks all!

 

You don't have lifters to tick in the first place. Sounds like piston slap or possibly a exhaust leak.

 

I know that piston slap was more common with the 1997 F150 4.6L, so it may be that (same lower end).

My uncle was told that piston slap was not really something to worry about, and his truck kept going reliably to 170k miles before he sold it (it was still running great when he sold it).

 

On my 2002 F150, with 4.6 engine, the cam chain guides were worn out! The chain eventually wore a hole in the oil pump cover. Cost me $1800.00 to replace the oil pump and cam chains and guides. My mechanic ,who works on a lot of high mileage Triton engines,say is normal for these engines with 150,000 or more miles. Hope this helps!! Johnny G.

 

What were your symptoms leading up to the point at which you knew there was a problem, and what were the symptoms that made you finally take it in?

I think the rest of us would like to know if the same is happening to ours.

 

I've heard the noise for the timing chain guides failing is similar to a sewing machine and of course would always make the noise.

 

It was an intermitant tick at first. I was towing a trailer on a vacation. by the time I got home it was sounding like a diesel engine. I ran it for approx. 3,000 miles before I did anything about it. I asked a mechanic who works for a used car dealer who sells alot opf trucks what he thought the problem was. He told me and sure enough when I took it in they found worn out guides and a hole in the oil pump cover. I am not saying that this is your problem,I asm just relating what was my experience. My guy says that my truck is good for another 150,000 miles. Thanks, JohnnyG.

 

If it was worn out guides you would think the noise would be there all the time. I bought a stethoscope to try and locate the noise. From what I can hear it sounds like loud tapping (clacking) from a few injectors. Its such a hard noise to diagnose. It clacks till the engine is warm than its gone. Do injectors warm up ??

 

I changed lifters in my truck just last week due to a tick. Also replaced the push rods and rockers too. The tick o's completely gone, just not sure as to which replacement cured the noise. The lifters and rockers/rods were all showing acsessive wear to them. ---I have a 4.2L though---- not sure if there's too much difference. Hope it helps..