Ok I have a 2000 Ram 3500 4x4. I just installed brand new heads, new exhaust valves, new valve springs, brand new O2 sensor, new plugs, wires, cap, rotor. I did the whole top end.

The problem I have is that it seems like my truck does not put out the power it should. If I push on the gas hard from a dead stop it tries to take off but it becomes sluggish. When I am driving on the highway its kind of tough to maintain a certain speed. Any ideas? I checked my fuel pressure at the rail and I was holding steady at 50psi.

Also, I found a little oil leak behind the engine by the distributor. Upon inspection it seems the back piece of the intake manifold gasket has slid out when I was reinstalling the manifold. This wouldnt cause these symptoms though would it?

Thanks for any help. Its important I get this truck running right because I have a tree service and its a dump truck that I can not afford to just run like ****.

 

stick or auto? what size tires? gears? stock? has it always ran this way for you or did you just buy it this way?

 

Need to fix that gasket, it can cause major problems if you dont.

If you messed with the distributor (took it out) need have a shop set fuel sync with a scanner

What 02 sensor? If it isnt a denso its probably causing problems. Especially if its a bosch

 

It's all stock. I bought the truck this way which is why I decided to do the top end. Upon removing the heads I seen the valve seats were shot and there were cracks in them which is why I bought new heads.
I changed to the front passenger side O2 sensor. As far as the gears I am not sure and it is an automatic.

There are no CEL on.

 

Vac leak is first problem with that gasket jacked up. Check for vac leaks anywhere else as another thing to rule out.

 

What about your cat?

 

Im starting to wonder if maybe my fuel injectors are going bad. Ill check all the lines for vacuum leaks but I can say that i changed the old brittle plastic lines with new rubber lines and there isnt any hissing under the hood. Im scratching my head now and it is a little aggravating. I just threw $1300 under the hood and its still not up to par. Grrrr

 

Two brand spankin new cats, although they are universal, they are brand new. Also brand new mufflers.

 

Alright. As HamBone said, what brand of 02 sensor? NTK is stock on these trucks, anything besides that or sometimes Denso will make it run like crap.

 

well, to be honest, it is a bosch O2 sensor.