Hello, and today I borrowed and connected the clock and the remote control according to instructions. The system pressure was not really right, because I had a short time over 6 bar, but as soon as I opened the button the pressure fell abruptly. To exclude everything I connected the fuel supply after description and noticed that the pressure is not even held for 5 seconds. Maybe this explains my bad cold – and warm start?! If my question is: I think that the check valve is definitely defective, because all lines are tight. Is the check valve in the pressure storage tank or in the petrol pump? By the way, the petrol pump is also noisy, I don’t think it’s normal. Thank you very much for the Audi Coupe Type89 NG 5 cylinders 11/1988