car jerking dont know why!

[khsdm]

when i go from 4th to 3rd and really step on the gas, booost will go to like 13psi and sounds what seems to be venting but it jerks terribly, don't have a clue what is going on. if any ones had this problem please let me know

 

[GTM]

when i go from 4th to 3rd and really step on the gas, booost will go to like 13psi and sounds what seems to be venting but it jerks terribly, don't have a clue what is going on. if any ones had this problem please let me know

It could be your BOV is sticking, letting off too much pressure, slambing closed and then popping off again etc. Is your boost gauge changing when this happens? Other than that possibly spark plugs and or wires could be going south and developing a miss.

Cheers,
GTM