i put a shiny red box under my hood a couple of days ago, connected it all up (gotta love that harness!), and everything was running fine. i just noticed a problem though. i went to go check the timing today, disconnected the EST, adn the car wouldn't start. it would run for a split second and then die. but if i put my foot on the gas a little, it starts, shoots to 2500 rpms, revs up fine, but the second i let off the gas and it hits 1000 rpms it dies. no sputters, coughs, misfires, it's like i turned the key off. it runs perfect otherwise, besides the off idle hesitation that's been there for 20k miles. any ideas? 87 V6 camaro

 

Knock any vacumn lines loose ?

check for loose vacumn lines