How to test for fuel pressure in 3.0 engine. Can't find a schrader valve.

Hello. Thanks for replying. Just found I could reply. Ok, reviewed, inspected previous work. Checked wire/ vacuum hose connections. Found nothing. But did a few tests. Made sure rotor actually rotating. Retest for spark. Every plug/coil, ok. Then removed rubber air intake duct from throttle body, opened throttle plate, first squirted brake cleaner and crank engine. No start. Then tried Starter fluid. No start. This has me completely baffled. As the fuel filter/pump are difficult to access, especially fuel line connectors, given the no start with spark and manual fuel insert... I don't see the point now. Something completely foreign to my logic is occurring and I haven't got a clue now. Only thing that comes to mind, are the new plug wire connectors, which have an "angled" connector. They are very difficult to insert on the plugs. Can't feel a *snap* onto plug. Feel loose..very easy to pull out of recess. However, my spark test was with a DIY spark tester made from plug which I removed the "L" thingy, and cut back threaded portion `1/2". Clear view of strong spark, which should jump even if connector not fully engaged on plug. I'm baffled. Will wait for your suggestion. Thank you.

p.s. In regards to the exhaust gas in cooling system, as I explained earlier, when the misfire problem first raised it's head, I checked radiator, and coolant was low. Couldn't see it. However, there was small bubbles. I added coolant directly into radiator instead of reservoir. The next day, it dawned on me, perhaps, because reservoir was empty, system was sucking air from reservoir instead of coolant. I then filled reservoir, drove to town and back. Began misfire after engine warmed up above normal. Checked radiator again with engine running. Could see coolant flowing...and NO bubbles whatsoever. However, haven't had time to delve into fan problem. Too busy with engine start first. God I hate modern cars. :)

One other observation. Even if one cylinder was misfiring from blown headgasket, it would still run, as I drove 50 miles with misfire..and then it STOPPED misfiring 5 miles from home. This tells me something. But after front bank plug change, it started and ran smooth...no misfire. Except it ran retarded, and lack of power when test drive...like old school vacuum advance hose was leaking. Haven't got a clue now. Thing is, engine light is on, and closest place to read codes is 35 miles from my home. Did I mention I hate modern cars. :)

If it started OK, then went to a no start right after some work was done, then the first things to check are something not connected correctly related to the work that was done or a blown fuse.

Hello again. Thanks for reply. Update: Checked all fuses and relative relay sockets. Exchanged fuel pump relay with adjacent same type relay. Crank engine. Still no start. Re-examine wire harness' and vacuum hoses. Discover wires to Throttle Position Sensor covered in electrical tape by someone previous. Thinking possible shorts as I moved this wire harness while changing out plugs, decide to remove tape. Discover all three wires with open insulation, but not adjacent. Cut out all sections and solder new sections in place with shrink tubing over joints. Then, test TPS power/and ground with harness disconnected from sensor, to known tolerances. 4.6V @ power, 12V @ ground with reversed probes, Red to positive battery terminal/Black to ground terminal at connector. Ok. Reconnect, and probe signal wire and test while manually slowly moving throttle from closed to open. .8V closed, 3.6V fully open. Voltage values within known spec. Sensor Ok. Re-open rubber air duct at throttle body, open throttle, respray starting fluid. Re-connect duct. Crank engine. Still no start. I'm baffled now. However, still have to test Cam Position/Crank Position Sensors, and Fuel Regulator/pump and filter. Btw, from knowledge gained from research, it appears the PCM(ECM) should be ok due to spark test. But I could be wrong. Don't know specific test for proof PCM is ok. Please inform me if you know. All I know now is I'm baffled why no start with spark and starting fluid fuel. And wife is getting upset as we are stuck at home for 2 weeks. Live in small Michigan town with no auto repair, and closest auto parts store with code reader is 35 miles. Moot point with no start. *Sighs*

BTW, re-test for spark. Everything ok. Plug wires and coil. 3rd re-check of work. Found nothing. Only removed alternator wires/plug wires and coil wire. Had wife crank engine while I moved around various wire harness'. Nothing. I'm still baffled. Still wondering if blown Fan relay has something to do with this. Can't find anything online regarding this. Will test today. Also, just for proof, removed distributor cap and had wife crank engine. Rotor turning. No broken timing belt. Moot. Spark test should have proved this.