Hello Everyone,

I have a 2003 Dakota SLT, 4.7L V8. It has 121,000 km (75,000 miles) on it.

Recently when I start it up I hear a pretty significant tapping or knocking noise. It increases in volume and frequency when I press the gas. This noise is the worst right when I start the truck up, and diminishes as the truck warms up, to the point where after the truck has been running for some time it's pretty much gone. I took a short video to capture the sound, and zoomed in on where it sounds like it is coming from
It sounds like it's coming from the motor on the left side if you're standing in front of the truck looking at the engine. I did a little research and thought that it might be a fallen rocker arm but I don't want to go through all the work to get at that part of the motor if I don't actually know that's the problem.

Another thing is I'm getting a check engine code P-0441 which is "Evaporative Emission Control System Incorrect Purge Flow" Here is a link to a description http://www.obd-codes.com/p0441

I don't think any of the symptoms of this code would cause the sound that I'm hearing.

So in conclusion I'm very confused as to what's going on, I'd like to try to fix it myself if possible but I can't identify exactly what the problem is and I don't want to take it in to a mechanic yet as I'm trying to avoid a costly repair if possible.

Thanks in advance for any advice or help anyone can give me.

 

If it goes away after its warmed up its probably the exhaust manifold either leaking or cracked.

 

I'm going to agree manifold it will heat up and close the leak

 

I would fix the problem with the code just to make sure there was no issues. Then start tracking down the noise. I would think that if it was a crack in the manifold, It would be leaving some kind discoloration or something. Maybe a leak around the exhaust gasket? Hydraulic lifters will make noise when the engine is cold. It could be your seals are going bad.

 

dose the noise increase speed when you press the throttle... if so id say lifter.... but my 2000 Dakota dose the same thing and its an exhaust leak from the audio it sounds like mine. and my CIL is on also

 

All sounds are different when listening on a PC , but remove the valve cover and check for a broken valve spring or collapsed lifter. Is the engine missing on a cylinder?