for research look up lower intake gasket replacement. that will give you all you need to get down and find any coolant leaks in the intake system.
as for figureing out if you have an intake leak. Like said, pull the plugs and look there. I would also look to see if your coolant is low at all... check in the radiator too if it if very low you could have a leak in the intake as the coolant had to go somewhere.
if it doesnt start i would go from ground zero and start from scratch.
1) Pull plugs check for coolant like said, if they look lean or rich, any damage, then a compression check if the plugs look fine. If good on to next step
2) Fuel pressure check at rail. if you can find one to rent an injector test light. but a fault in the wiring is rare.
3) Spark as long as one wire from each coil pack throws a spark from the terminal to the wire both will be good 9/10 cause its a loop system.
all you need is air fuel spark and it will fire. if your close to stock you can pull the battery to reset the fuel trims on the PCM and then disconnect the MAF and start it. will go into limp/ open loop mode. its all about ruling out variables.
when my DOHC jump time i pretty much had to run thru the big three scratching my head cause everything looked fine on the fuel and spark section. the DOHC is AL head so i didnt want to pull the plugs and strip them. also i was without my compression tester anyway. a compression check would have told me imediatly that i had a problem. later when i tore it all down i had air blowing out the intake side of the heads!
