Hi im new to all this forums but im hoping someone will know the answer and be able to help?
I have an audi a4 1.9 TDI 130 AWX with the dreaded limp mode caused by overboost, ive changed the N75, ive changed the Turbo, ive checked the vacuum lines and they hold a vacuum for hours, the vnt nozzle moves freely, ive checked the ohms on the N75 ive cleaned the EGR and intake manifold, according to VAG my MAP and MAF are working, ive done a cycle test and all sollenoids are working , ive checked the voltage to the N75 and at idol its 10.5 volts, ive checked all connections for rust and there fine but as soon as i hit 3400rpms in 4th gear it goes into limp mode. If i drive it for about 30 mins at high revs it will go into limp mode a few times then its fine but the next day its just the same, limp mode!!!
I have no idea what else it could be and hope someone out theres had the same problem and found the cure?
Thanks Mark