[ChrisS]

My nearly completed Sportster is based on an M52TUB25 engine. The ECU was remapped by Ergen Motorsports to overcome the immobiliser/canbus issues.
The guy finishing the car for me has overcome a number of bad connections in the engine loom and had got the engine running OK. But it has suddenly stopped. Almost as if the work done by Ergen didn’t actually do the job.
Am at the point where starting to wonder if drawing a line under the current engine might be the best way forward. If so what would go in relatively easily and avoid all the challenges of the the TU variants?
Would a plain M52 engine drop straight in mechanically and not need the various security mods that the TU needed?
Any other obvious choices?
It was due to be booked in for IVA shortly having just got a new windscreen from Marlin. So this is pretty frustrating.
I am going to try another remapped allegedly stand-alone ECU. But if that doesn’t work then wondering if a complete change is on the cards.