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i need some help i got a 5.3 i rebuilt. dropped into my tahoe and no start. well first i figured out im not getting spark.so my plugs are brand new and my ignition coils are fairly new. but i cannott get any resistance to come up testing coils but they worked fine a few weeks before ,i did have a bad random misfire and some knock but i advanced my timeing plus 2.any ways i noticed no oil pressure at all while cranking, so now im building a pressure pump to prime it with.this is my first rebuild im new to all this i bought a pc some engine books and a shit load of tools and im hooked. well please someone give me a hand with this its ****in up my life and marriage.if any one has some ideas call me or txt 8104934779. i really need the help. thank you johnny deere

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Check all your grounds, especially the ones on the back of the cylinder heads. Also double check all your PCM connections and all fuses. You probably just overlooked something. 

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Have dropped in many a rebuild myself.

Check your wiring and ground points.

Air,fuel,spark. Check spark with a timing light. Check fuel pressure on key on.

On initial start, you should disconnect the spark igniter harnesses so the engine cranks at very low speed in order to allow oil to flow though out. You can verify some flow by checking oil filter to see if it is full.

Ps. Remove your phone number. Ask people to pm you and you can exchange phone numbers.

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