My Truck Sputters then goes fine...

[jeremywrags]

Hi All,

My truck is sputtering when I am barley on the throttle. Once I pass a certain point in the throttle everything seems fine. Also I think this is related but when I take off from a stop, I get a little hesitation and then bam it takes off. I am thinking something wrong with the carb any advice?

75 K5 Blazer - 350\TH350\NP203 4BL Eldelbrock with Performer RPM manifold.

 

[J.R.]

might want to start with checking for vacuum leaks, bad plug wire...

 

[496truck]

Sounds like a problem with the accelerator pump in the carb.

BUT

Check the simple and obvious things first, fuel filter, ignition system, vac leaks, etc... Make sure everything is up to par before getting into carb repair/rebuild/replace.

 

[jeremywrags]

So I am not the most mechanically inclined person and am still learning, how do I check for vacuum leaks?

Fuel filter is new, Plugs& Wires are new

Thanks

 

[yellowmedicine]

Just look for bad hoses and listen for air leak sounds. You can use a section of fuel line or other hose and hold 1 end to your ear and check around with the other end. Check fittings, around carb base, etc...

 

[gotblazers]

Sounds like maybe a bad vacuum advance.

 

[496truck]

Fuel filter is new, Plugs& Wires are new

Good start. How about the dist cap and rotor? How about the timing?

You guys in CA don't have spray carb cleaner available to you, right? Something like that can be used to help find vacuum leaks. A physical check of all the lines is best though.