bmw 740i remote starter

having trouble with transponder using factory ews transponder with key and relay dosent seem to  work all the time  any help appreciated with possible other transponders or anouther way of doing this

What kind of bypass module are you using? On BMWs and Volkswagens with the transponder keys I've had trouble getting them to work by running the ring antenna around the fact. antenna; I've had to attach the wires from the bypass directly to the factory antenna wires.

im using the factory ews2 transponder ring with a key and a relay ,  to trigger the transponder antenna to simmulate the key in the cylinder , its actually a dei tech tip. if there is any other  way of doing this it would be nice . because the way i have it the system only seems to work about 40% of the time for some reason. that factory system energizes the chip in the key appon startup and changes the value everytime.