silverado 4.3 engine not firing on number 5
 

i replaced intake manifold gaskets because had bad water leak did that ok put all back but missing on number 5 ,had new plugs and leads ,compression test on 3 and 5 both read the same.

hi took truck to garage today for diagonistics only come up with number 5 not working ,he did compression test on 5 and 3 both the same reading,came home took top inlet manifold off and changed number 5 injector to number 3 put it all back pulled plug lead off 3 engine makes a change, pulled number 5 no change ,so it now has new plug and wires,injector changed and still the same i just dont know what to look at ,it has good spark any help please its not loosing water or over heating starts from cold

Try swapping plug wires from #5 to a cylinder you know is firing. You may have gotten a bad wire or possibly a bad plug. What year truck is this?

hi its a 2000 4.3 did the same on old leads and plugs ,garage said it could be distributer shaft got airline crack in it ,so any help will be good thanks dave in uk