02 ford f150 crank, no start but randomly.

make sure battery has a full charge and connections all good. Do testing when problem is ongoing. Have helper crank it while you visually check for spark at the plugs. If spark everywhere, use a gage and check proper fuel pressure, check fuel injector pulse? Any applicable trouble codes? Those are the basic checks, in my opinion. Some fords have maf sensor problems, where applicable. On a ford, you can unplug that sensor, then see if it will start and run ok? If it does, I'd have to check maf system and wiring circuits.

Spraying some starting fluid use to make it fire right right up, now its having more and more trouble starting. But now prob. 60% of the time it starts up with no issue. Maybe once a week it will also try to stall i guess? It feels the fuel was cut off, mid drive. But comes right back to. It recently ran and started perfect for 3 or 4 weeks, and were back to this.

Thanks, I've checked spark on a coil over, I've not checked exact pressure up ontop. Try the MAF here in a bit, only code is the EVAP code p1451.

As far as the code goes, I'd check the evap canister vent valve. Open voltage should be close to battery voltage and closed should drop from that by at least 4 volts. Also make sure all the vacuum lines are properly connected. As for the no start situation, if you have good spark clear through, from the info given, I would look into fuel pressure at the fuel rail and injector pulse. The fact that it runs great when driving (for the most part) suggests that the timing is good, I would also check air filter and mass airflow sensor. Any idling issues combined with the aforementioned issues would hint at the idle air control valve