Z22SE Car stalls continously driving me crazy

hi, I have an astra from 01. Its running on both lpg and petrol. For while I have this problem that the engine stalls when I stop at the lights. sometimes it stalls when I press the gas pedal hard from idle, driving or not its the same. I looked around and could not find anything about it. this stalling really drives me crazy
The EML is off, I cleaned the throttle body last month also blanked the egr off together with a cheater as adviced on this forum. I am glad I did, runs better now. but still has this stalling problem. It goes to low revs where it shakes the car and jumps back whenever I stop at some traffic light.
I changed the air filter and spark plugs to platinum last week. Both of the chains has been done in november since it was rattling :eek:

I will do that one Kevin. Does the CTS of VX220 also fit the Z22SE, I looked at your guide and they look the same.
I recently converted it to LPG. It happend in june. At the LPG garage they told me that the lpg side of the car is good. The car runs worse on lpg than benzin. The revs doesn't drop low that it shakes on benzin but it does stall randomly on it sometimes. This is very rare on benzin tough.