Hello Rev4K,
we had exactly the same problems when those Roadster Series 1 came onto the market. MIL very often on and mostly P0171 and P0174 have been the faults. We could nearly cure all our customer cars from their suffer by doing this:
Taking off the Morgan self made air box. In front of the air flow meter Morgan did glue in a kind of wire mesh or better an expanded metal mesh. This shall protect the air flow meter for bad air streaming.
We simply did fit a second expanded metal mesh and glued it in. This did improve how the air flows around the air mass meter.
Very simple and over here very successful
Regards Frank
