cold start sputtering

[apachiestrike95]

i have an 1985 720 4x4 with the z24 carburated motor in it, earlier this year it started to sputter in 1st and second from 1k rpms to 3k rpms but only when it is cold, on top of that my fuel mileage dropped to about 10mpg, ive had the carb rebuilt, replaced the  o2 sensor, coolant temp sensor, fuel pump, and exhaust manifold. The sputtering isnt as aggressive as it was but it still does it and my mpg is still garbage. ive done done plugs and wires and ignition coils as well and it didnt seem to change anything. it was able to pass smog on its own and better than most modern cars. im tired of dealing with its morning bitchiness and would love any guidance on to what could be causing my truck to be a twat. p.s it does have a a rebuilt motor in it along with head work done to it all before i got it, the motor has about 60k miles on it currently. 

[Veraciousreasoning]

I am having a similar problem where my 1980 just is shit in the morning. 

[datzenmike]

Does the choke come on when cold?

[apachiestrike95]

24 minutes ago, datzenmike said:

Does the choke come on when cold?

nope

 

[apachiestrike95]

59 minutes ago, Veraciousreasoning said:

I am having a similar problem where my 1980 just is shit in the morning. 

mine does it more than just the morning, it does it whenever it sits for an extended period of timr. its just a cunt really

 

[datzenmike]

19 minutes ago, apachiestrike95 said:

nope

 

 

Don't you think that something designed to make the engine run richer and smoother while warming up might be a good idea the get working ?????????????????????

[apachiestrike95]

4 minutes ago, datzenmike said:

 

Don't you think that something designed to make the engine run richer and smoother while warming up might be a good idea the get working ?????????????????????

well the thing is it isnt just in the mornings that it does it 

[datzenmike]

Once the engine cools off or sits, perhaps at work? the engine is cold and the choke sets. It needs to be fixed so that it works and then if there are additional problems we work on them knowing that it isn't the choke.

[apachiestrike95]

3 hours ago, datzenmike said:

Once the engine cools off or sits, perhaps at work? the engine is cold and the choke sets. It needs to be fixed so that it works and then if there are additional problems we work on them knowing that it isn't the choke.

the place that i had the carb rebuilt at siad they fixed the choke, but it dont work for shit and id rather not go back there since i brought it to them with the issue and had to bring it back because it had the same issue and they blamed it on me saying it was my fault that it was doing that. 

[datzenmike]

In the morning when the engine is absolutely cold, take the top off the air filter and look. The choke flap should be partly open. Step on gas 2-3 times.... the choke flap should snap fully closed. Does it?