I bought a Fi Tech Go4 600 in 2015, didnt go into service till 2017 in the restoration. Engine has been making good power and mileage (hot cruiser) but I've always been making adjustments. 2018 they sent me a warrentee fuel injector (sticking, running rich). 2019 they sent 2 more and I bought 2 to change all four, same problem but different position in the TB. A couple of weeks ago I'm cruising and it's running sweet until I get a couple of hickups and after I shut it off, wont restart. Fuel pump is not working, changed the FP. Started but when warm it wouldn't restart. I checked the 6 pin harness, the FP connection is burnt. Bypass the connector and it starts and idles, even has water dripping from tailpipes (condensation, not coolant), AFR is staying at target. Until it gets to 170* and goes closed loop, AFR starts cycling from 10 to 20 some of the 5 day old injectors are shutting off and coming back on, others are running rich (trying to compensate maybe) and RPM is all over the place. Called FiTech and tech says probably ECU. Sent the TB back to Riverside and now I'm waiting for a diagnosis. If it's needs an ECU and nothing else shipping, parts, labor I'll be in for another $600 ish. I liked the EFI until now, I just dont know. Maybe carb in my future, hope not. Maybe all my adjustments and parts changed was the ECU all along from start.
