buzz test?

[CstoberDamm]

Will a 7.3 run if all 8 injectors fail the buzz test?

[ryandamo]

sometimes yes but it will be extremely hard to start if the solenoids are worn

[CstoberDamm]

My truck is starting up great since I had 6 glow plugs & my block heater cord replaced. But since having those items replaced I have no up hill power. Before checking the glow plugs they told me I needed all 8 injectors to fix the hard start.
Once I got the truck started it ran great the morning I dropped it off at the mechanic. It was doing 70 mph @ 2000 rpm in od as it has since I bought it a few months ago. On the return trip home & the last few days it will only pull 2000 rpm @ 30 mph up hill. It seems to run fine down hill or along the flats.
Could anything have been left unplugged from the glow plug replacement that could affect just the up hill performance?