1994 truck
 

I have a 1994 Silverado Z71 5.7. It idles fine but as soon as you put it in gear and give it gas it sputters and wants to quit then it takes off. any ideas??

is that EFI or carb?

No. They havnt put carbs on since 86. Its fuel injected

Buy a vacuum gauge and read THIS. Sounds like a vacuum leak or fuel pressure, so check the fuel pressure also. Could be timing, fuel filter/bad gas or a clogged CAT also, the vacuum gauge should narrow it down.

What happens when you rev it up not in gear?

its none if those. we checked for vacum leak and checked fuel pressure and it was good. we checked the timeing and that was good too and replaced the fuel filter.

when its not in gear it runs fine

we just replaced the throttle body gasket and then took it for a drive.. it hesitats on acceleration now

Did you hook it to the vacuum gauge?

No we checked the lines and there not leaking and a buddy of mine is a mechanic and he said there not leakin either

Cansome one help me figure out whats wrong with my truck?

put the vacuum guage on and read the gauge.... what is it doing