
$150.00 to pull plugs?! That's crazy. Start with the basics, fuel and spark. Make sure there is fuel getting to the injectors, if it is check the spark. You can use a new spark plug to check it. Pull on wire off any plug, ground it and watch for a spark. I think I'll lean towards it being a fuel issue.
Is this a 4 or V6 motor? When the motor turns over, does it spin the same as it did when it ran or does it spin faster? If it spins faster, check the timing belt or chain, not sure which one this one has. If it spins faster than normal, could the timing belt or chain need to be changed.