Hey everyone,
I have an ls swapped 72 firebird with a T-56 transmission on.
I had someone tune it for the first time at my house (Cause I didn't have the clutch bled, windshield, hood, brakes). Just wanted to have it turn on to break in the new engine.

Here's what happened:
The first couple of start ups sounded great! the engine ran pretty good. He turned it off, then turn it back on and BAMM! a huge jolting that feels that it came from the trans tunnel. It completely stopped the engine. Sounded terrible. I was very confused. He then tried the ignition again and the car turns on fine again? I have no idea why I would be getting this issue. Tuner guy says that its definitely not the engine.

Could It be that I need to get the clutch bled? perhaps the transmission is getting caught on the slave cylinder? Do you need to depress the clutch as you turn on the engine?

Sorry for my lack of understanding...

 

Welcome to LS1Tech!

You have to push in the clutch to start most manual cars and it's always best to be in neutral when starting the engine.

 

You also need to make sure that when you push in the clutch that your not pushing the clutch slave to far into the pressure plate.