Intermittent problem

Help pleeeeeeeaaaaasssssseeee!!!!!!!!!
My 1.6 petrol Z16XE 2004, has a problem, harder to start than normal, engine light is on and at 3000rpm kicks and splutters, then will eventually clear itself then drives fine.
So far I've had the coil pack done, crank sensor replaced and cam speed sensor replaced.
Makes it better for a couple of days then returns, normally happens when the engine is stopped and started a couple of times, stopping for petrol then shopping.
Only fault code showing is P0335 on pedal test

both the crank and cam sensor are oem 

Any ideas, I'm at my wits end and wallets gone on strike