93 rodeo 3.2 2wd crank but no start

Yes, the ECM is the last thing to replace after all other possibilities. No spark could be bad ignition coil, bad Ignition Control Module (controls the coil circuits for spark), bad plug wires, the crank and cam sensors (for ECM to determine spark timing).

Check the ICM -it can be tested at a parts store. If good, check the crank sensor.

Once it starts does it run OK or does it take a while to "come out of it"? What is the weather like? How is it acting when it wont start; does it turn over, if it cranks does it fire at all or no ignition at all, do you smell gas while it is cranking?

You say it has fuel pressure, if it has sequential fuel injection it needs about 70psi to start the engine.
If it cranks and has spark to the plugs, the anti-theft system is not involved.
You did not mention the rotor, I assume you have spark to the plugs not just out of the coil.
If you have not yet checked cranking fuel pressure, I would start there. The pump could be weak or the filter stopped up.

To clarify, if it turns over it cranks.
If you know it is not getting spark to the plugs, you will need to have someone check the rest of the ignition system including cap and rotor, module, and pickup coil in the distributor. (V6)
The first thing a mechanic would do is make sure the coil has voltage.

If the starter cranks very fast when you are trying to start to check for spark, it is a possiblity that you have a busted timing chain. This explains the rapid sound of you starter engaging, because the crankshaft is not being turned and the camshft is not either therefore no spark is made.

is the check engine light on ! if so it could be a bad crank sensor doing this. no spark and no fuel pulse to injectors. if both go off together then its the crank position sensor. There are three primary engine malfunction symptoms that may be indicators of CPK malfunction. If the vehicle engine is experiencing cylinder misfires, the CPK may not be providing the computer with accurate information on piston position. If the vehicle hesitates during acceleration, the CPK may not be providing cylinder position data to the computer fast enough to fire the appropriate cylinder to accelerate the vehicle in response to driver input. The most serious indication of CPK malfunction is intermittent start, and eventually no start. When the sensor fails, the computer will register a malfunction code and illuminate the check engine light on the instrument panel. good-day !

We will star a list of what is good.and what controls spark
1. crank sensor .you done it
2.ignition control module. located on the center of bulkhead,behind intake air hose
3.coils. you tested it.
4.ECM located under passenger side foot well

ECM no you got fuel,so lets leave it out
cranksensor okay you replaced it
ICM ignition control moduel.
no spark you cover everthing. has to be a loose or no contact connection somewhere, you covered it all.you might want to tap on the ecm., or check the fuse for power to junction the ones in the hood area those can blow and not give power to ignition system

There is no simple answer, there are to many variables. If you have access to a scan tool, pulling the codes should help. Without them its back to old school hunt and peck method. At this point we need to narrow down the problem. You need to test for spark.

1. Tag and disconnect the spark plug wires from the spark plugs.
   
2. Remove the spark plugs and install the spark plug wires to each spark plug.
   
3. Ground (do not hold spark plug) the spark plug; check if spark occurs while engine is being cranked.
   

Crank the engine for no more than 2 seconds at a time to prevent flooding the engine with gasoline.
If you have spark, You will want to make sure you have fuel injector pulse, along with fuel pressure. If you have spark ..simply spray some starting fluid in through the air filter and hold the gas pedal to the floor and crank it over while spraying. If it fires up, you know it is fuel related( fuel pump, regulator, or ECM if no injector pulse) . If you have no spark then look at ignition coil connection and trace through to the distributor( if equipped ). The crank shaft sensor has a tendency to fail on these as well. This should give you a few things to test and check to start you on your way to narrowing it down. If you have no spark then look at ignition coil connection for power and trace through to the distributor( if equipped ). If it is DIS( no distributor). It may be the Crank sensor or the ECU. The crank shaft sensor has a tendency to fail on these as well.
The ECU uses the signal sent from the Crank sensor to trigger the spark and fuel injectors. ( make certain you have checked all fuses)

pickup coil in the distibitor bad or if tbi or multiport
change the crank sensor / cam sensor last ignition control moduel

When it won't start check for spark , pull a spark plug wire an hold it near ground (metal on the engine ) have s helper crank the engine . Is there spark ? If no check power an ground at the ignition control module , check control . In side the ignition module are transistors ,these energize the coil (control spark ) It can be tested with a test light . Check out scanner danner videos on youtube . But if there is spark , spray some starting fluid into the engine throttle plate an see if it starts then . If it does you have a fuel problem .