97 7.3 loud knocking

[jcass29]

hi all. i have a 97 mason dump w/7.3 i lent the truck to my cousin he said when he started the truck up after setting for a couple weeks it sounded like it was missing and when he gave it fuel it made a loud bang and started knocking. my question is where do i start to even look for a problem? he thought it was a rod and started the procedure to take the engine out, the more i read im thinking it might be a injector but dont know how to check. the oil was drained and there was no metal in the oil which futher leads me to believe its and injector. has anyone had this problem before and can you offer me any advice.
thanks
jimmy

[fragglerock2000]

hi is the cheack engine light coming on
when it knocks and does it come and go

[jcass29]

i havent got the truck back together yet, almost there but theres a wiring problem now, when i was reconnecting the batteries the truck tried to start when i connected the negative cable.. so now we have to figure out why, my cousin disconnected all the wires so im not sure where they go. any help would be appreciated.

[jcass29]

no power in the cab , anyone have a idea? what might not be hooked up correctly

[Isakson]

is ur starter hooked up right? and u may have blown a ignition fuse under the hood...might check that. if u wanna check ur injectors have a mech scan it and run a buzz and contribution test, more than likely one will fail i had the same miss and knock and it was several injectors. i replaced one then i could hear another knock and replaced it, then just replaced all of em. how many miles ur truck got on it??? and u might check to see if it has 2 o rings or the single o ring..that was an update on the obs 7.3's

[jcass29]

i got it back running and it is a weird knock , like its coughing back threw the air box or something along those lines. running rough and knock missing..if that makes any sense. we are going to check for codes , but we dont have the equipment for a buzz test,ill have to take some where unless someone knows another way to check.
thanks

[jcass29]

ok my cousin has a otc genisys and it was able to do a buzz check and it said all 8 injectors are good. can anyone suggest a next step. also i dont know if this matters but i had the cam position sensor replace by the dealer as a recall about 50 miles before all this started.

[Isakson]

u need to do a compression test... this will tell u if u hav good injectors, injectors may pass a buzz but fail the compression.....

[Isakson]

i kno all mine passed the buzz test, but 8 Failed the compression test

[jcass29]

how can i do a compression test or is it something i need to have a shop do? was yours coughing threw the intake. thats what this sounds like, and my cousin said when it started making the noise it made a loud noise like something broke, its not a rod knock . i dont think.