Hi, I'm looking for help. We got a 1991 ls400 and recently it went into limp mode with unburned fuel smoking out of the exhaust. Car won't accelerate past 5pmh and rev past 1500rpm. No check engine code. When I try reading it with obd 1, the check engine light just flashes really fast. I got 2 ecu units from a pick n pull, both from wrecked 91 ls400 with the same part number. Nothing has changed. Has anyone experienced a similar problem?