Quite right, Roy. As you'll note in my second post, that started to dawn on me later. I said I was no K-Jet expert -kinda obvious.

Technically speaking I'll say a B21FT does have an ECU, but around these parts when anyone is talking ECU they're generally talking a computerized FCU with some kind of IQ like the LH Jetronic system. ECU is a term that refers collectively to all components of the engine management system which are primarily electronic, as opposed to mechanical or electrical. That includes the FCU (fuel/air stuff) plus ICU (ignition stuff).

Now see if I've got my story straight. The K-Jet system on an '84/'85 turbo (B21FT) includes:

o the Bosch TZ pointless ignition system, with input from the induction coil in the distributor, which provides a timed spark;

o the constant idle system consisting of the CIS control unit, with inputs from the ignition coil (rpm), throttle micro-switch, A/C micro-switch and block temp sensor, which controls the idle speed by way of the idle air valve/motor and an idle boost solenoid valve;

o the K-Jet injection system consisting of the Lambda-sond control unit, with inputs from the O2 sensor and turbo pressure switches, which controls the fuel mix by way of the frequency valve which is ahead of the purely mechanical control pressure regulator (CPR) and fuel distributor (operated by air flow damper) which feeds the injectors.

Some of the more common no-start problem areas in the above appear to be bad frequency valves, bad Lambda system relays and bad wiring harnesses. The electronic units themselves are considered fairly robust.

Is that better?