Intake popping and sputtering

[Mizark347]

My freind has a 87 Gt with a stock motor. No EGR or smog. When the engine is cold and just started up. The engine gets really ruff, intake pops, and power is really down,it all happens through every gear under about 3000 RPM. This all goes away once its up to operating temperature. New cap, rotor, plugs. Motor has about 130,000 on it. could be a lean mixture, bad O2 sensor? what does detonation feel like? Any help would be great, thanks.

 

[Mike86Stang]

Check your timing & check for vacumme leaks. Those are my bets.

 

[bock]

vac leak... i had this pro... was a vac leak .cracked hose. you know? those f***ing cheap plastic hose that crack just by looking at it!!!

Took them all off and put rubber hoses.