I am not sure if anyone can help bacause I don't know if I can describe this nut here goes.

I have an 01 F250 V10 I recently bought it with 110k miles. The truck is only used on the weekends. When it sits for a few days and I fire it up it makes a fairly loud noise as soon as it fires up. Its hard to describe the noise, but its like loud Vibration noise that lasts for about a fraction of a second. It only does it once extremely breifly then everything works great. I can count on it every time the truck sits for a while.

anyone experience this?

 

When this noise occurs is the heater on or is it in defrost mode. I have heard a similar sound and I'm pretty sure it is the AC compressor making that noise. If I put the heater control to the vent mode no noise when I start the truck.

 

Seems like I've heard similar complaints about the heater/AC air flow damper. Guess it depends on what you mean by a "fairly loud noise"!

 

I guess the best way to describe it is to say that it is loud enough to suprise you but not like a backfire. It seems to be comming from the left of the engine compartment. There are two broken studs on the manifold on that side. I wonder if that could be part of it.

 

Sure could, but first you should check your spark plugs to be sure they aren't loose. The earlier V10's didn't have enough threads and could blow the plugs out once they begin to wobble.

 

I said front left, but I meant front right of the engine compartment

 

Driver's side or passenger's side?

The AC compressor is on the passenger side.

 

I had 2 2000 V10s still have one of them and the one I have has always had a rattle when it was started after setting for a few days. The other one never did. I think mine may be lifter noise or maybe exhaust noise or even ejector noise ( my old 351W had ejector noise when it was cold). Its been doing it for 7 years without any problems so far and I have heard it in other V10 also. It happens so fast that its had to track down so I just don't even worry about anymore.

Denny

 

Could it be a piston slap?

 

It may be but it doesn't sound like what I call piston slap and it goes away faster than the piston could expanded from heat.

Denny

 

Mine make a noise like a clutch is engaging or a belt is almost off (not squeeling). Almost like a clunk when the engine first starts and revs. It stops in one or two revaloutions. My 5.4 in my van is the same. I was wondering if it was the A/C compressor, belt tensioner or clutch fan. I also can't track it down. My truck only has 38K on it and it has been doing it since almost new. My van is a 06 and has 21K on it and the same thing.

 

Does it remind you of landing gear going up or down when your sitting in a plane? My '03 did that on startup when I left the A/C or heat on last time I drove it,I would guess it was the damper either closing or opening rather harshly.

 

Open the hood up & have someone else start the engine while you listen for the noise .

 

I have a 97 e350 van w/ v10, when i start it has a knocking noise on the passenger side. You can barely hear it sitting in the van with the passenger window up. But, out side it makes a tapping sound. Mine is very loud for about 30 sec, goes down, but still can hear for 5-10 min, then it goes away completely.

From the front with the hood open you don't hear it much, the fan and all drown it out.

From the side it sounds like it is coming from underneath and the back of the engine or trans.
When i take the inside engine cover off (this is a van), and i use a socket extension to listen around, it is on the passenger side, toward the back.

And, I just noticed a broken exhaust manifold stud back there. But, this sounds like a clack in the engine.

This has 220k on it. I got it at 186k, and it had the noise when i got it, but it is getting worse. Well, it had the noise After i did an oil change. The person who sold this to me put something thick in the oil to quite it, so it made no noise when i bought it. When i took the oil filler cap off it had a thick white foam at the top of the filler pipe (what would that have been? white grease?). I changed the oil right away, and that is when i started hearing the clacking. So, doubt it is a piston.

I have used a number of oil additives (that say they reduce wear on start up) - like Lucas, Slick 50, and others. They help only slightly. Otherwise i use 10-40 synthetic oil only.

BTW - I have had 2 plugs blow out on this thing. After i am done with my current work contract, end of year, i am selling it. Will be looking for a 2006 or 07 as i heard they fixed the plug problems in 06. (I retapped the threads slightly, used hi-temp silicone rubber on threads, and got them on tight, so far they have held. The first about 20k so far so good. But, to do it right i have to take the heads off and get proper inserts put in. That will run big $$$. I guess i had better take the time and check all my plugs on that side, they are so hard to get to on a van. But, i don't want another plug blowing out.)

Bookum, anything above sound similar?

 

If it's a rattly type noise it may be the timing chain before the hydraulic tensioners have a chance to recieve oil pressure. To a point, and as briefly as you say it happens, I would consider it normal. Sitting all week adds to my suspicion that this is what you're hearing since they have plenty of time to leak down. By the way the tensioners have a racheting type catch that keeps them from retracting completely but your chain may not be worn enough to allow the tensioner to extend to the next catch. Motorcraft oil filters have an anti-drainback valve to help with that too.
On my '04 F250 I was so in tune to this sound that when I started the engine cold in the morning I could tell when it needed an oil change because the sound would change slightly, usually every 2,900 to 3,400 miles, change the oil and it would go back to normal.