Dear Steve,Thank you for your reply,
Running problem was cured by cleaning the tank filter, spot on
As for the ABS,
Shuttle valve switches, both open (brakes off) 2977 to 3067
Shuttle valve switches, both closed (brakes on) 2977 to 3067 (No change when brakes are applied)
All earths are in good condition, re-made to be on the safe side.
Yes, the code comes back straight away.
Customer is on the lookout for a second-hand modulator, not keen to spent 2 grand on it...
Thank you for your help