ldefoggi

I have a 1998 F150, with a 4.6l. It has about 183K miles. Over the last few days when ever I start it up I get a rattle or clunking noise for about 1 second. It's not a heavy sound, or a sound like thin metal. It almost sounds like valve knocking I used to hear on my 4.0 (push rod) V6 explorer... only louder. My mileage seems to be about the same and my cylinder head and coolant temps are normal. Does anyone have any idea what this could be? I changed the oil about 2 months ago and it has about 1300 miles. I checked it after the first time I heard it and it was low by about a quart. I filled it up and went on with my day thinking that was it but I still hear it.

It has been unusually cold here, in the 30's for the last two days or so...

TheUnforgiven71

Let me guess RGV? and do you hear it with you accelerate on the highway

ldefoggi

RGV?? What's that?

No, only during startup after it's been sitting for more than 5 hours.

TheUnforgiven71

Rio grande valley, south texas, so no noise when the engine is already warmed up

ldefoggi

Oh, no I'm in Jacksonville, FL.

Nope everything seems and sounds normal when it's warmed up. It sounds like valves to me but I guess it could be anything (water pump or a pulley?) Maybe I'm just being paranoid but I'm thinking its a sign of problems to come....