what grounds or what not, just the whole slew of stuff that has a hand in it.
thanks

 

Fuel injectors have "no grounds".
The signal (from the ECU) is a pull-to-ground.
The other side of the circuit is switched on once your key hits ON or START.


-Ted

 

1. Cranking speed under 500rpm
2. Water thermo sensors output to the ECU.
3. Input from the *starter* circuit to the ECU.
4. AFM not used during START
5. See the attached graph.

https://www.rx7club.com/forum/attach...hmentid=150448

 

so if you water temp sensr was bad that could contribute to hard starts then?

 

IF disconnected or a broken wire from the sensor to the ECU, then it would be very hard to start when the engine was COLD. Because the fuel amount injected would be too little.

BUT once the engine was fully hot it would not make for a difficult start BECAUSE if the signal from the sensor is lost, the ECU defaults to a temp of 175 F. That equates to a fully warmed up engine so the fuel amount injected would be close to normal.

1. More fuel injected when the engine is cold.
2. Less fuel injected when the engine is hot.

 

127,210 miles would contribute to a hard start.. or not the best compression.