So my Mazda axela 2005 3i has the same problem, But the weird thing is my check engine light is not on at this point but the computer has picked up the code p0661,Iv been told it's possibly the 2x fuel rail vacuum solenoids which is a common issue with these cars so I have replaced this and cleared the code but it's come back up so it's been taken to a auto electricians could be wireing problem etc, Will update when I have the answer��