It will only fire with starting fluid. Either cold or hot. Runs fine after, but will not re start on own. We replaced cam sensor, crank sensor, temp sensor, pressure regulator, and distributor cap.

engine light on ..any other fault codes

changed coil ..still the miss fire

could it be cam shaft sensor or crank angle sensor

are plugs leads and injectors working ?

All the time ? Cold or hot doesn't matter ? ETC- engine coolant temp. sensor . What engine ?

I would expect to find a problem with the fuel pump or the injector pump loosing their prime.
Usually if a sensor is faulty the check engine light is on.

try this it may work as i dont know your area, as im in uk but remove the air temp sensor on the filter box and see if that works, if it does it could just need replacing or you need a remap to the ecu as its reading the wrong signal. could even be a bad connection to the ecu so might just need a good clean on the ecu connector.

Sounds like a bad ignition control module when it gets hot.

Check the spark coil block and the crank sensor.

HI, ok lets address each issue as your asked 1. Timing belt: since this engine uses a timing chain and it runs fine for the most part its unlikely to be the cause. 2. Ignition module: well the module not only sends the signal for spark timing but it also uses another signal for the fuel injectors. Since these ignition modules are very sensitive to heat the module may fail only when it is hot. So yes it could be the ignition module. 3. A fuel problem: Because you have fuel that sprays a foot high does not mean it has proper pressure. think of it as a garden hose the water flows out the end of the hose normally but when you place your thumb over the hose it squirts harder. You are trying to release the fuel from a much larger fuel rail threw a small shrader valve. Electric fuel pumps are little motors turning at very high rpms. when they get hot after use they draw more amperage and produce less volume and pressure. So yes fuel could be the issue. 3. Injectors clogged: Your right unlikely but you may want to do a resistance check of the injectors while cold then one while hot. You may find even one shorting out after it gets hot and this will shut down the whole bank of them. 4. Crank sensor: the crank sensor sends a pulse to the DIS module the ECM then controls the demand for fuel and timing. These crank sensors are prone to cracking and letting oil wick into the sensor apply heat and it can raise the resistance and make the sensor fail till it cools. So yes the crank sensor can cause this type of no start. 5. Cam sensor: no this model 3.1 did not use a cam sensor. 6. Intake gaskets: this would have to be one very large leak when hot. you could try pouring oil over the intake gasket area while cranking and see if it fires over. The oil is should be heavy and thick enough to seal it for a short time or show where it sucks it in. a few things you over looked are the importance that the temp sensor and TPS sensor play during a hot start. If the ECM thinks that the engine is cold it uses injector pulse like a choke on a carburetor. Good luck on your adventure I hope this has helped.

could be the injectors are worn, the fuel is not atomizing. dribbling more than spraying.

take it to a volvo dealer and have the codes read
most likely a coolant temp sensor, ambient temp sensor, Baro sensor, MAP/VAF sensor problem the fault codes will tell you

it could be an engine heat sensor or water temp sensor.