Below is a list of what's needed for starting. Basically it's spark then fuel. See how far your car is progressing, so you can focus on the right area....
Start-Run Sequence LH 2.2 Version ['85-'88 240]
1) During starter cranking, the distributor Hall sensor sends timing pulses to Ignition Control Unit (ICU) located below windshield fluid tank.
2-a) The ICU uses these Hall Sensor pulses to trigger the Ignition Coil (– terminal) to initiate timed sparks from the coil.
2-b) At the same time, the ICU also propagates the pulses to the FI ECU, to allow FI operation. [ lack of ICU pulses means no Fuel pumping]
3-a) The Fuel Injection (System) relay (previously energized at Key On) powers the AMM and ECU. The System relay lives with the Fuel (pump) relay in the same white plastic case. The LH 2.2 "pump" relay also powers the Injectors, IAC motor/valve, and the O2 sensor heater.
3-b) When ICU pulses are received by the FI ECU, it "energizes" the Fuel (pump) relay by grounding the relay coil (– side) to run the pumps.
When all these things work, the engine runs until the Ignition is switched off, which in turn shuts down the FI system.
Determining whether or not there is spark at the plugs (2a) — and whether or not the plugs are getting gas (3b) — are good no-start "starting" points.
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Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
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