First: note where the noozle hole is pointed and then You can remove the old one by using a small adjustable wrnch, the noozle has a flat side on it, I just twisted mine like I was unscrewing it and it came out, be careful not to lose the the check valve and note which way the pointed end on the vlave is when you reinstall the new noozle. When you install the noozle, just tighten it like you would a screw, make sure it is seated.
Im guessing you have a carb, the accelerator pump is in it.
32mm keihin with accelerator pump
Pump is on front of Carb. square panel with four screws.
On my engine,the accelerator pump on the Carb is going bad, 350 engine with quadrajet carb
About 1/64" from bottoming out when throttle is wide open.
first of all is it injectors or carb, if a carb it could be a bad accelerator pump
if it runs fine until you push the gas pedal the accelerator pump may be bad if it has a carb on it.
a double pumper is a 4 barrel carb. commonly made by holley. they were called this because they have two accelerator pumps. one on each float bowl on either end of the carb. most carbs do not have this feature, they usually only have one accelerator pump.
carb problem my guess would be accelerator pump or stuck power valves in carb.
make sure the timing is right, no vacuum leaks, or the carb could have a bad accelerator pump in it.
If it has a carb. (not fuel injected) one possible cause could be a bad accelerator pump (located in carb.).
timing might be off or the carb is loading up /too much fuel or has a faulty accelerator pump.