I have the following symptoms:

1. Hard to start

2. Engine knocks only when it's cold, after it reaches operating temps no
knock.

3. Thumping/knocking exhaust sound constantly. Similar sound to a blown
head gasket, but not as drastic.

4. Engines runs rough when torque converter locks ups in 4th gear and rpms
are below 1800(turbos not spooled up good). Basically when the engine
is being lugged.

5. Fuel in water light comes and goes.

I had the injectors checked and that they were either cracked or spray pattern was way off. Was told the holes were made too big. Had the injectors replaced and fuel mileage increased, but still had the same symptoms.

Are these symptoms of a dropped valved or another issue?

 

You would know if it was a dropped valve. It will have a dead miss especially when you put it in gear. It will also have a knocking noise, however, when one of my injectors stuck open, it knocked worse than when my valve seat fell out. You'll have alot more smoke when your injector is dumping fuel in the cylinder and it knocks more when you accelerate the engine. With a valve you will get white smoke because that cylinder is not burning the fuel but it will not be excessive like with a injector dumping fuel. The surest way is to pull the valve cover and check for a valve that is real low, rocker arm real lose, or a valve that is high,rocker arm real tight, and or higher than the other valves. Once you pull the valve cover be sure to roll the motor over a little at a time and check the relationship between the rockers and the cross-overs for the valves for each of the cylinders when it is time for the corresponding cylinder to have the valves closed. If something isn't right you'll see it. I am dealing with that right now on my '05.

 

Thanks for the response.

I'm going to tear into it on Saturday and just trying to get an idea what to look for.

Anyone else had these issues?

 

my 06 dropped a valve. it was a constant knocking clattering sound. if you want to know what it sounds like exactly, take off your wrist watch and walk to the kitchen and put your watch in your blender and push the high button....

 

I'll be doing mine about the same time if you need a another head to bounce info or questions off of, pm me and I'll give you my phone number. I'm finishing an overhaul on a NTC 855 cummins at work on friday maybe part of Saturday but after that I will be tearing into my truck also. I hope everything goes well for you. Joseph

 

Plans have changed and I won't get to mine til Monday. I'm confident it's something internal and hopefully I've caught it early enough not to have major damage.

I appreciate the help and will be in touch.