N00b needs a lil' help

[ButtJuice]

When I start my car and accelerate, usually in the morning or at night, my car sputters and won't pick up much speed. This will happen for about a minute, then finally it'll shape up after being warmed up for a little. What would cause this? ..Also I'm getting shitty gas mileage for an ETA. I'm sure there are many possible culprites, o2 sensor, afm, ect.. ect.

Any thoughts?

[billybobjoseph]

Test your coolant temperature sensor

[Cabriolet]

cold start injector just died on you, i bet.

[jaywood]

cold start injector just died on you, i bet.

Doubt that. Cold start injectors only run for a couple of seconds

[lostatoll]

I have this exact same problem. stumbles around 1700 - 2400 rpm, only when the engine is cold. Once warmed up it's totally solid throughout. I don't think it's the CSV, and I've replaced the rubber intake boot that had a crack thinking it was an air leak. Should I check the AFM?

I don't know if I'm getting really bad gas mileage, I drive almost all city, and am at 21mpg right now. I could probably do better. What do you guys think, It would be really nice to solve the stuttering.

[lostatoll]

how could the coolant temp sensor play a roll in this? please explain maybe?

[Gruelius]

on my megasquirt car when the warm up enrichment was poorly tuned it would stumble when cold and feel like its choking

[MTechnikII]

"how could the coolant temp sensor play a roll in this? please explain maybe? "
when the engine is cold the gasolin condesates on the cylinder walls ,therefore the ECU sends more feul at the time of cold start to keep the engine idling smoothly, only way the ECU knows that the engine is cold is through th coolant temp sensor, when the engine gets warm the sensor reading changes and the ECU adjusts the fuel rate.
there are 2 coolant temp sensors on the thermostat housing , one is for the temp gauge and the other is for the ECU, you can figur out which is which byu unplugging one at atime and look at your temp gauge if it drops to cold then the ECU sensor is the other one.

Henry

[lostatoll]

Thanks Henry, you rule.