Finished a rebuild a while back and everything is great except for starting. I had a mechanic set the timing.

When I start it initially in the morning, somtimes, it sputters a little and check engine stays on a little longer than normal.

If I give it gas as I start it it's fine. Once it's warm and I start it, it's fine.

I remember a screw on the top of the air intake manifold for fuel, should I try adjusting that? I've made small adjustments to the timing but it's the same.

 

Injectors maybe clogged, low fuel pressure or clogged fuel filter. Any of these could cause fuel atomizing problems especially in a cold engine.

 

Should I try a fuel system cleaning additive, or does that have the same negative effects such as radiator stopleak and stuff like that.

I'll replace the fuel filter as it's only $12, injectors are quite a bit more.

So, the screw on the intake manifold is a no go?

 

Sounds like the cold start injector. Testing procedure is in the factory service manual.

 

I am not familiar with the screw in the manifold, Also I am new to these trucks so I was going by experience with other vehicles I owned. Referring to a previous post the cold start injector is probably the place to start.