97 Yamaha G16 gas

[norm0649]

I was asked to help someone with this 97 g16 cart which has no start condition. Engine cranks, starts, and stops immediately. I checked for fuel ( ok ), next for spark which was little to none. Suspected tci coil. Removed f/w cover checked coil visually. I had cheap one and it was 3/16" from flywheel once installed. Reinstalled old one and removed engine stop relay then jumped power to blue wire when cranking. Cart started and ran fine. Tried replacing eng. stop relay and cart won't start...back to jumper until I can figure out the problem! Wiring has being tampered with and I have to check all the grounds etc. The carts 40 miles away. I suspect coil may be bad. No spark unless powered direct. Could this be a ground issue???. Lots of wiring to check along with charging system. But looking for thoughts. I'm a retired truck mechanic not golf cart expert. Any help appreciated.thanks