A 305 engine may stall when putting it into gear due to several factors, including a faulty idle air control valve, which can disrupt the engine's airflow and cause it to struggle under load. Additionally, issues with the transmission, such as low fluid levels or a malfunctioning torque converter, can lead to stalling. Vacuum leaks or a malfunctioning throttle position sensor can also affect engine performance when engaging gear. Lastly, an improper fuel-air mixture due to clogged fuel filters or injectors can contribute to the problem.
EGR problem
You may need to adjust your idle speed or timing.
if an auto trans-in gear 550 <-it should speed up when you put it in park that should be 650---start with 550 in park--put into gear-if it wants stall turn it up 2942E6B7-0D26-E667-F7DC-E162A40E3ADF 1.03.01
Could be a bad battery or starter.
Hey, I got a 91' firebird 305 tbi that had the same exact problem...it's your speed sensor or O2 sensor....(or both)
it takes 2qtsof gear oil
Try changing the oxygen sensor.
There are a couple possibilities. First, the lockup torque converter could be stuck. It could be as simple as a faulty relay or it could be the torque converter itself. Second, it could be that the engine is not producing enough power to keep running when it's put into gear. For example, it could be idling fast because of a vacuum leak, but not really producing much power. When the transmission is engaged it could put enough power demands on the engine that it can't keep going.
a bad head gasket or intake manifold gasket.
broken fuel pump/ fuel filter can cause car to die right after starting. If the fuel pump is not pumping fuel into the engine, the car will stall.
Could be--valve not closing completely