I recently posted about my 98 S70 got not starting. I got some good info but after replacing the fuel pump, filter, fuel pressure regulator, cap, rotor, wires,plugs, TPS, ignition switch electrical side still won't run. Actually let clerify that, will run when using starting fluid and would run for a few minutes after 5-6 recranks and feathering the accelerator. I am at at total loss, ANY SUGGESTIONS GREATLY APPRECIATED.

 

Fuel system relay? Do you have 12v at the pump when trying to start? Whats the fuel pressure? Any codes? Air mass meters fail - but don't replace it until you diagnose it as being bad.

 

Ok, being that it will run using starting fluid points to a fuel delivery problem. I know this may sound nutty, but I once had a coolant temperature sensor go bad that caused almost the same issue. The coolant temperature sensor is a small sensor located just below the thermostat and actually screws into the thermostat housing. The function of the sensor is to send the coolant temperature to the computer to tell the computer how much fuel to send to the engine based on engine temperature. The sensor can fail in two ways....one, it can give a constant hot temperature signal, which will cause the computer to send very little fuel to what it thinks is a warm engine (when actually it is cold). This will make the engine very hard to start and need constant feathering of the accelerator to run until the engine actually warms up, then it will run properly (this was my problem, and the telltale clue was that the dashboard temperature gauge went to mid level as soon as I turned the key, even though the engine was stone cold). The second way for the sensor to fail is to give a constant cold engine signal to the computer. In this case a cold engine will start and run normally, but get worse as the engine warms up. Worth checking out.....the sensor is easy to change out with very little loss of coolant.

 

A few minutes is a long time.

The PCM operates the temperature gauge, so look at that. Get a scan tool and look at the measured temperature, measured throttle angle, measured air flow. We can give you some baseline numbers to compare to.

You may have a big vacuum leak. You may have low fuel pressure.

 

did you check the injector relay (a gray box up front near the radiator)? are the injectors getting a pulse?