Since it starts with starting fluid it must be a fuel issue, not a timing issue, or a bad crank position sensor. Had your mechanic installed a fuel pressure gauge at the fuel rail to see what type of fuel pressure you have when the engine isn't starting? If the fuel pressure is good, you might have a problem with the computer telling the injectors to fire. No injector pulse means no gas in the cylinders.

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2006 Infiniti G35
2001 BMW 3.0I E53 X5 Build date 08/2000 SOLD
Lotus Europa 1970 Destroyed by fire
Lotus Europa 1970 S2 Renault Powered
Lotus Type 52 1970 Twincam Webers Powered
PORSCHE 911 Targa 1982 The Garage Queen
Audi Avant donated to Kars for Kids
BMW 525IT Sold
Audi 4000CS Quattro Sold
Jensen Healey Lotus Powered Sold
Opel 1900 Sold
Triumph Spitfire 1971 Sold
Triumph Spitfire 1968 Sold
Plymouth "Cuda" 340 Six pack SOLD