Air sensor pot ? Check the voltage on the center terminal should be between 0.5 and 1V, ideally 0.7V. Note that the wire connector must be plugged into the sensor pot to do this test.

Coolant temp sensor ? It is the last sensor on the engine, towards the windshield. The resistance should be between 2.5K and 3.5K when cold and between 250 and 350 ohms when engine temp is 80 degC. This sensor is very important, it sends signals to both the fuel compuiter and the ignition computer.

Injector seals ? Spray some carburettor cleaner around the seals and see if rpms get affected. In general, any other fuel leaks ?

Intake manifold seals ? Again try spraying carburettor cleaner at this and various places where you suspect vaccum leaks. Did you measure vaccum at the intake manifold ? It should be between 16-22 Hg on the vaccum gauge.

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Saumil S. Patel