You could have gummed up the piston rings enough to cause really low compression. Try putting an ounce of brake fluid or Marvel Mystery Oil(MMO) in each cylinder. Let it sit as long as you can let it, give it at least a day. You'll have to remove the injectors before you do all this or course. After it has sat for a while turn the engine over while having someone hold rags over the injector holes. This will blow out any excess brake fluid or MMO. Then put it all back together and try to start it.

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